1933 ACT FILE NO.: 333-195351
1940 ACT FILE NO.: 811-21056
CIK NO.: 1598626

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM S-6
AMENDMENT NO. 1

FOR REGISTRATION UNDER THE SECURITIES ACT
OF 1933 OF SECURITIES OF UNIT INVESTMENT
TRUSTS REGISTERED ON FORM N-8B-2

A. Exact name of trust: Advisors Disciplined Trust 1237

B. Name of depositor: Advisors Asset Management, Inc.

C. Complete address of depositor's principal executive offices:

18925 Base Camp Road
Monument, Colorado 80132

D. Name and complete address of agent for service:

WITH A COPY TO:

SCOTT COLYER SCOTT R. ANDERSON
Advisors Asset Management, Inc. Chapman and Cutler LLP
18925 Base Camp Road 111 West Monroe Street
Monument, Colorado 80132 Chicago, Illinois 60603-4080

E. Title of securities being registered: Units of undivided beneficial
interest in the trust

F. Approximate date of proposed public offering:

AS SOON AS PRACTICABLE AFTER THE EFFECTIVE DATE OF THE REGISTRATION STATEMENT

[ ] Check box if it is proposed that this filing will become effective
on ____________, 2014 at _____ pursuant to Rule 487.

-------------------------------------------------------------------------------

The registrant hereby amends this Registration Statement on such date or dates
as may be necessary to delay its effective date until the registrant shall file
a further amendment which specifically states that this Registration Statement
shall thereafter become effective in accordance with Section 8(a) of the
Securities Act of 1933 or until the Registration Statement shall become
effective on such date as the Commission, acting pursuant to said Section 8(a)
may determine.

The information in this prospectus is not complete and may be changed. No one
may sell units of the trust until the registration statement filed with the
Securities and Exchange Commission is effective. This prospectus is not an
offer to sell units and is not soliciting an offer to buy units in any state
where the offer or sale is not permitted.

PRELIMINARY PROSPECTUS DATED JUNE 6, 2014

SUBJECT TO COMPLETION

ARMR MLT(SM) SERIES 2014-1, S&P 500(R) PORTFOLIO

(ADVISORS DISCIPLINED TRUST 1237)

A dvisors A portfolio seeking
--- capital appreciation linked to
R eference the S&P 500 Index and
--- repayment at scheduled trust
M arket termination of [$1,010] per unit,
--- subject to the credit of a reference
R eturn issuer, along with the potential
--- for income

M arket
---
L inked PROSPECTUS
---
T rusts ____________, 2014
---

As with any investment, the Securities and
[LOGO] Exchange Commission and Commodity Futures
Trading Commission have not approved or
AAM disapproved of these securities or passed
upon the adequacy or accuracy of this
ADVISORS prospectus. Any contrary representation
ASSET MANAGEMENT is a criminal offense.

------------------
INVESTMENT SUMMARY
------------------

MARKET LINKED TRUSTS

This trust is a "Market Linked Trust". AAM's<F1>* Market Linked Trusts are
unit investment trusts designed to provide an amount per unit linked to a
market reference.

INVESTMENT OBJECTIVE

The trust seeks capital appreciation linked to the S&P 500 Index (the
"Index") and repayment at scheduled trust termination of [$1,010] per unit,
subject to the credit of a reference issuer ("the Reference Issuer") along with
the potential for income. There is no assurance the trust will achieve its
objective.

PRINCIPAL INVESTMENT STRATEGY

The trust seeks to achieve its objective by investing in options linked to
the Index and the credit of the Reference Issuer (the "Options") and U.S.
Treasury obligations (the "Treasury Obligations"). The Reference Issuer refers
to ____________________. The Options have a scheduled expiration date of
____________, 2020. The counterparty to the Options is _______________ (the
"Option Counterparty"). The Treasury Obligations consist of interest-bearing
obligations issued by the United States Treasury and are backed by the full
faith and credit of the United States government.

The trust is designed to provide an amount per unit at scheduled termination
of (i) [$1,010] plus (ii) [$1,010] times the percentage price appreciation in
the value of the Index from [__________, 2014] to [________, 2020] minus [2%],
subject to a cap of [40%], so long as there is no Credit Event (defined below)
with respect to the Reference Issuer. If a Credit Event occurs with respect to
the Reference Issuer, no Index-linked return will be paid and instead the trust
is designed to provide an amount per unit at scheduled termination of [$202],
resulting in a significant loss. In addition, the trust is intended to provide
semi-annual payments of interest income from the Treasury Obligations to the
extent interest income exceeds the trust operating expenses. The estimated net
annual interest income per unit is [$3.36] as of [____________, 2014] as shown
under "Investment Summary--Essential Information" and may vary thereafter. In
addition, if the Option Counterparty is bankrupt or otherwise cannot pay its
obligations when due, the trust may suffer losses or be unable to achieve its
investment objective and it may result in a loss on your investment.

Credit Events are described in more detail below and generally include
material adverse credit events, such as bankruptcy, insolvency, dissolution or
liquidation of the Reference Issuer, the failure of the Reference Issuer to make
payments on any of its obligations for borrowed money including any payments
with respect to a specified Reference Obligation (as defined below). The
Reference Obligation refers to the following corporate bond:

REFERENCE OBLIGATION
NAME OF ISSUER, REFERENCE
INTEREST RATE AND OBLIGATION
MATURITY DATE CUSIP
----------------------------------------------------------------

___________________________________ _________

The foregoing discussion applies to an investment in units held over the
entire life of the trust if you purchase units at the regular public offering
price on the trust's inception date. Illustrations of the trust's investment
strategy and how the Options work appear under "Understanding Your Investment--
Option Expiration Examples" in this prospectus. Additional information about
the Options and the Reference Issuer appears below.

The Index is an unmanaged index of 500 stocks listed for trading in the
United States that is maintained and published by Standard & Poor's, a division
of McGraw-Hill. The Index is market-capitalization weighted and generally
representative of the performance of larger stocks traded in the United States.
The Index is determined, composed and calculated by Standard & Poor's without
regard to the Options or the trust.

--------------------
<F1>* "AAM," "we" and related terms mean Advisors Asset Management, Inc., the
trust sponsor, unless the context clearly suggests otherwise.

2 Investment Summary

THE OPTIONS. The Options provide for the Option Counterparty to pay the
trust [$1,010] multiplied by:

* the Index Ratio-[2%]

* subject to a minimum of [100%] and a maximum of [140%]

per trust unit at the Option expiration date so long as no Credit Event (defined
below) has occurred with respect to the Reference Issuer at any time prior to
the Option expiration date. If a Credit Event occurs with respect to the
Reference Issuer at any time prior to the Option expiration date, the Option
provides for the Option counterparty to pay the trust [$202] at the Option
expiration date. In either case, the trust is obligated to pay the Option
Counterparty an Option premium of [$1,000] at the Option expiration date.

"Index Ratio" in the formula above and throughout the prospectus denotes the
closing level of the Index on [_____ , 2020] ("Index Final Value") divided by
the closing level of the Index on [___________, 2014] ("Index Starting Value").

The Treasury Obligations are pledged as collateral in order to secure payment
of the trust's obligation to pay the Option premium to the Option Counterparty
at the Option's expiration. THE OCCURRENCE OF A CREDIT EVENT WITH RESPECT TO
THE REFERENCE ISSUER WILL ENSURE A NET PAYMENT ON THE OPTIONS FROM THE TRUST TO
THE OPTION COUNTERPARTY (I.E. A LOSS TO THE TRUST). The Option Counterparty is
not required to pledge any collateral to secure its payment obligations to the
trust at the Options' expiration.

For the Option to obligate the Option Counterparty to make a net payment to
the trust at the Option expiration (i.e., for the price of the Options at
expiration to exceed the premiums payable by the trust), the Reference Issuer
cannot experience a Credit Event prior to the Options' expiration date. The
occurrence of a Credit Event prior to the Options' expiration date will result
in the trust making a net payment of [$798] to the Option Counterparty on the
Options at the Option expiration date and no Index-linked return will be paid.

THE REFERENCE ISSUER. The Reference Issuer was selected by AAM after
considering feasibility and indicative pricing for the potential option
contract. Only issuers of corporate bonds rated investment grade quality as of
the trust's inception by at least 2 of Moody's Investor Service, Standard &
Poor's and Fitch's Ratings were considered. Investment grade corporate bonds
are rated BBB- or higher by Standard & Poor's or Fitch's Ratings or Baa3 or
higher by Moody's Investor Service. These ratings are based upon an evaluation
by a credit rating organization of the corporation's credit history and ability
to repay obligations. An investment grade rating generally signifies that a
credit rating agency considers the current quality of a bond to be sufficient to
provide reasonable assurance of the issuer's ability to meet its obligation to
bondholders.

The Options are not designed to provide a return that is the same as the
return on the Reference Obligation or any other securities issued by the
Reference Issuer. The Options do not provide exposure to interest income paid
on the Reference Obligation. The return on the Options depends on whether a
Credit Event occurs with respect to the Reference Issuer prior to expiration.
If, in respect of the Option, (a) the Reference Issuer mandatorily converts,
redeems, exchanges or replaces the Reference Obligation into or for any other
securities or instruments or (b) the Reference Issuer is subject to an event in
which one or more entities assume or becomes liable for all or a portion of the
Reference Obligation or other obligations of the Reference Issuer or issues
obligations to be exchanged or substituted for the Reference Obligation or other
obligations of the Reference Issuer (such as a merger, demerger, consolidation,
amalgamation, spinoff or transfer of assets or liabilities), the "Calculation
Agent" (which is generally the Option Counterparty) shall be entitled to (i)
adjust any term of the Option as it determines appropriate to preserve the
theoretical value of such Option to the parties immediately prior to such event
and (ii) identify one or more substitute reference obligations and (iii)
determine the effective date of such adjustment or substitution, as the case may
be.

Investment Summary 3

CREDIT EVENTS. A Credit Event with respect to the Reference Issuer includes:

(1) Failures to Pay: where after the expiration of any applicable grace
period (after the satisfaction of any conditions precedent to the
commencement of such grace period), there occurs a failure by the
Reference Issuer to make, when and where due, any payments (a) with
respect to the Reference Obligation or (b) in an aggregate amount of not
less than $1,000,000 under one or more obligations for borrowed money, in
each case in accordance with the terms of such obligations at the time of
such failure.

(2) Bankruptcy: where the Reference Issuer (a) is dissolved (other than
pursuant to a consolidation, amalgamation or merger); (b) becomes
insolvent or is unable to pay its debts or fails or admits in writing in
a judicial, regulatory or administrative proceeding or filing its
inability generally to pay its debts as they become due; (c) makes a
general assignment, arrangement or composition with or for the benefit of
its creditors; (d) institutes or has instituted against it a proceeding
seeking a judgment of insolvency or bankruptcy or any other relief under
any bankruptcy, insolvency, rehabilitation or conservation law or other
similar law affecting creditors' rights, or a petition is presented for
its winding-up or liquidation, and, in the case of any such proceeding or
petition instituted or presented against it, such proceeding or petition
(i) results in a judgment of insolvency or bankruptcy or the entry of an
order for relief or the making of an order for its winding-up or
liquidation or (ii) is not dismissed, discharged, stayed or restrained in
each case within thirty calendar days of the institution or presentation
thereof; (e) has a resolution passed for its winding-up, official
management or liquidation (other than pursuant to a consolidation,
amalgamation or merger); (f) seeks or becomes subject to the appointment
of an administrator, provisional liquidator, conservator, receiver,
trustee, custodian or other similar official for it or for all or
substantially all its assets; (g) has a secured party take possession of
all or substantially all its assets or has a distress, execution,
attachment, sequestration or other legal process levied, enforced or sued
on or against all or substantially all its assets and such secured party
maintains possession, or any such process is not dismissed, discharged,
stayed or restrained, in each case within thirty calendar days
thereafter; or (h) causes or is subject to any event with respect to it
which, under the applicable laws of any jurisdiction, has an analogous
effect to any of the events specified in clauses (a) to (g) (inclusive).

EARLY OPTION TERMINATION OR LIQUIDATION. The trust has the right to
terminate all or a portion of the Options prior to the expiration date by
tendering such Options to the Option Counterparty. This might happen to satisfy
unit redemptions, pay trust expenses or in certain other limited circumstances
to protect the trust as described in this prospectus. Upon certain
circumstances laid out in the option agreement, the Options may be terminated
early upon determination by the Option Counterparty. This may include, but is
not limited to the trust terminating early or the Option Counterparty being
unable to hedge the risks associated with the Options or having the cost of such
hedging increase materially. This determination as to whether to terminate the
Options early will be made by the Option Counterparty at its sole discretion.

If the trust or Option Counterparty exercises its right to terminate all or a
portion of the Options prior to the expiration date, the Option Counterparty
will be obligated to terminate such Options and make a payment to the trust in
connection with such termination. The payment owed to the trust on such
terminated Options will be calculated by the Calculation Agent (which is
generally the Option Counterparty) and the Option agreements obligate the
Calculation Agent to do so in good faith and using commercially reasonable
procedures. At the time such Options are terminated early, the trust will be
obligated to pay a discounted Option premium to the Option Counterparty in an
amount determined by the Calculation Agent using a discount rate determined by
the Calculation Agent in a commercially reasonable manner.

4 Investment Summary

You may realize a return that is higher or lower than the intended return at
the scheduled Option expiration in certain cases, such as redeeming your units
prior to the trust's mandatory termination date, where Options are terminated
early by the Option Counterparty, or otherwise liquidated by the trust prior to
expiration. An early termination of the Options may result in the sponsor
electing to terminate the trust early and/or the trust being unable to achieve
its investment objective and result in a reduction in the value of your units.

OPTION COUNTERPARTY. Neither the units nor the trust are sponsored,
endorsed, sold or promoted by the Option Counterparty and the Option
Counterparty does not act as sponsor, depositor, underwriter or promoter of the
trust. The Option Counterparty (i) does not make any representation or
warranty, express or implied, to the investors in the units, (ii) is not
responsible for and has not participated in the determination of the timing,
prices, or quantities of the units be issued, and (iii) has no obligation or
liability in connection with the administration, operation, marketing, sale or
trading of the units.

The Option Counterparty may be unable to make payments in the future if and
when due. The trust's ability to achieve its investment objective will depend
upon the ability of the Option Counterparty to meet its obligations. If the
Option Counterparty defaults on any payment that becomes due to the trust, the
trust may suffer losses or be unable to achieve its investment objective and it
may result in a reduction in the value of your units and result in a loss. If
the Index Final Value is greater than the Index Starting Value (i.e. an increase
in the value of the Index) and the Option Counterparty becomes insolvent, you
should not expect to receive any capital appreciation linked to the performance
of the Index. If the Option Counterparty becomes insolvent and the trust is
owed a net payment on the Options from the Option Counterparty, the trust may
not be able to recover any such amounts owed. If the Option Counterparty
becomes insolvent and the trust owes a net payment on the Options to the Option
Counterparty, the Options may be terminated early and the trust may be required
to make this payment prior to the Options' scheduled expiration date. This
could result in a loss to the trust on the Options prior to the Options'
scheduled expiration date where a loss may not have otherwise been experienced
if the Options were held to their scheduled expiration date.

PRINCIPAL RISKS

As with all investments, you can lose money by investing in this trust. The
trust also might not perform as well as you expect. This can happen for reasons
such as these:

* SECURITY PRICES WILL FLUCTUATE. The value of your investment may fall over
time.

* THE OPTION COUNTERPARTY MAY BE UNABLE TO MAKE PAYMENTS IN THE FUTURE IF AND
WHEN DUE. The trust's ability to achieve its investment objective will
depend upon the ability of the Option Counterparty to meet its obligations.
If the Option Counterparty defaults on any payment that becomes due to the
trust, the trust may suffer losses or be unable to achieve its investment
objective and it may result in a reduction in the value of your units and
result in a loss.

* THE FINANCIAL CONDITION OF THE REFERENCE ISSUER OR OPTION COUNTERPARTY MAY
WORSEN OR ITS CREDIT RATINGS MAY DROP, RESULTING IN A REDUCTION IN THE VALUE
OF YOUR UNITS. This may occur at any point in time, including during the
primary offering period.

* THE TRUST DOES NOT GUARANTEE ANY RETURN OF PRINCIPAL.

* THE TRUST IS SUBJECT TO INDEX PERFORMANCE AND EQUITY RISK. The Options
represent indirect positions in the Index and are subject to changes in value
as the Index rises or falls. The value of the Options may be adversely
affected by various factors, including factors affecting the Index and the
value of the underlying securities. The Index consists primarily of
large-capitalization stocks, the returns of which may vary from those of the
overall

Investment Summary 5

U.S. stock market. The value of the Index will fluctuate over time based on
changes in general economic conditions, expectations for future economic
growth and corporate profits, interest rates, the supply and demand for
large-capitalization stocks in the U.S. and other factors. Although common
stocks have historically generated higher average returns than fixed-income
securities over the long term, common stocks also have experienced
significantly more volatile returns. Common stocks are structurally
subordinated to preferred stocks, bonds and other debt instruments in a
company's capital structure, and represent a residual claim on the issuer's
assets that have no value unless such assets are sufficient to cover all
other claims.

* THE POLICIES OF THE INDEX SPONSOR AND ANY CHANGES AFFECTING THE INDEX OR THE
INDEX CONSTITUENTS COULD AFFECT THE MARKET VALUE OF THE TRUST AND ITS UNITS.

* THE TRUST IS EXPOSED TO RISKS RELATED TO THE REFERENCE ISSUER THROUGH ITS
INVESTMENT IN THE OPTIONS. Where a Credit Event occurs with respect to the
Reference Issuer, the trust will be required to make a net payment per trust
unit at expiration on the Options (the trust would incur a loss on these
Options). Options liquidated prior to expiration will be valued by the
Calculation Agent (which is generally the Option Counterparty) in a manner
that takes into account the value of and outlook for the Index and the
creditworthiness of the Reference Issuer. Investor perceptions regarding the
issuer of a bond are based on various and unpredictable factors, including
expectations regarding government, economic, monetary and fiscal policies,
inflation and interest rates, economic expansion or contraction, and global
or regional political, economic, and banking crises.

* IF THE OPTION COUNTERPARTY BECOMES INSOLVENT, THE TRUST MAY SUFFER LOSSES OR
BE UNABLE TO ACHIEVE ITS INVESTMENT OBJECTIVE AND IT MAY RESULT IN A
REDUCTION IN THE VALUE OF YOUR UNITS AND RESULT IN A LOSS. If the Index
Final Value is greater than the Index Starting Value (i.e. an increase in the
value of the Index) and the Option Counterparty becomes insolvent, you should
not expect to receive any capital appreciation linked to the performance of
the Index. If the Option Counterparty becomes insolvent and the trust is
owed a net payment on the Options from the Option Counterparty, the trust may
not be able to recover any such amounts owed. If the Option Counterparty
becomes insolvent and the trust owes a net payment on the Options to the
Option Counterparty, the Options may be terminated early and the trust may be
required to make this payment prior to the Options' scheduled expiration
date. This could result in a loss to the trust on the Options prior to the
Options' scheduled expiration date where a loss may not have otherwise been
experienced if the Options were held to their scheduled expiration date.

* BECAUSE THE OPTIONS' FORMULA HAS A NEGATIVE ADJUSTMENT OF [2%] WITH RESPECT
TO THE INDEX, THE AMOUNT REALIZED ON THE OPTIONS WILL BE LESS THAN ANY
APPRECIATION OF THE INDEX.

* THE OPTIONS AND THE TRUST ARE SUBJECT TO CAPPED UPSIDE CAPITAL APPRECIATION
RELATED TO THE PERFORMANCE OF THE INDEX. The Option payment related to the
Index and the trust return is subject to a capped upside. If the Index
increases more than approximately [42]% over the Index Starting Value as of
the Option expiration date, the amount realized on the Options will be capped
at [40%] and will be less than the appreciation of the Index.

* THE VALUE OF THE TREASURY OBLIGATIONS WILL GENERALLY FALL IF INTEREST RATES,
IN GENERAL, RISE. No one can predict whether interest rates will rise or
fall in the future.

* THE REFERENCE ISSUER COULD BECOME INSOLVENT OR BE UNABLE TO PAY ITS DEBTS OR
OTHER OBLIGATIONS IN THE FUTURE. Such an event would generally constitute a
Credit Event resulting in Options having the amounts due to the trust
significantly lowered but

6 Investment Summary

the premium owed by the trust to the Option Counterparty remaining the
same. If such an event occurs, the trust will not achieve its objective.

* THE TRUST IS EXPOSED TO RISKS ASSOCIATED WITH THE OPTION COUNTERPARTY WHICH
IS A COMPANY IN THE FINANCIAL SERVICES INDUSTRY. Negative developments in
the financial services industry may affect the value of your investment more
than would be the case in a more diversified investment.

* THE TRUST IS EXPOSED TO RISKS ASSOCIATED WITH THE REFERENCE ISSUER WHICH IS
A COMPANY IN THE _____________ INDUSTRY. Negative developments in the
___________ industry may affect the value of your investment more than would
be the case in a more diversified investment.

* THE RETURN ON THE OPTIONS AT EXPIRATION DEPENDS, IN PART, ON WHETHER A CREDIT
EVENT OCCURS WITH RESPECT TO THE CORRESPONDING REFERENCE ISSUER FROM
[____________, 2014] TO [____________, 2020]. The Options are not designed
at expiration to provide a return that corresponds with the return on the
Reference Obligation or general performance of the Reference Issuer's
securities. The return on the Option depends, in part, on whether a Credit
Event occurs with respect to the Reference Issuer prior to expiration.

* UNITHOLDERS WILL NOT HAVE CONTROL, VOTING RIGHTS OR RIGHTS TO RECEIVE CASH
DIVIDENDS OR OTHER DISTRIBUTIONS OR OTHER RIGHTS THAT HOLDERS OF A DIRECT
INVESTMENT IN THE INDEX CONSTITUENTS WOULD NORMALLY HAVE.

* THE TRUST MIGHT NOT ACHIEVE ITS OBJECTIVE IN CERTAIN CIRCUMSTANCES WHICH MAY
LEAD TO A LOSS ON YOUR INVESTMENT. These circumstances may include, but are
not limited to, if the value of the Index declines over the life of the
trust, if a Credit Event occurs with respect to the Reference Issuer, if the
Options are terminated early by the Option Counterparty or the trust, if the
trust terminates early, the units of the trust are redeemed early (as
described under "How Your Trust Works--Termination of Your Trust"), the
Option Counterparty defaults on its obligations, the trust disposes of
Options or Treasury Obligations to pay unit redemptions or trust expenses,
due to adverse credit factors affecting the Option Counterparty or due to
adverse tax law changes affecting treatment of the Options. The Calculation
Agent (which is generally the Option Counterparty) may exercise certain
duties which present a conflict of interest between the Option Counterparty
and the trust and may not consider the interest of unitholders when making
determinations.

* DISTRIBUTIONS OF INTEREST FROM THE TREASURY OBLIGATIONS MAY BE INSUFFICIENT
TO MEET ANY OR ALL EXPENSES OF THE TRUST. If the cash balances in the income
and capital accounts are insufficient to provide for expenses and other
amounts payable by the trust, the trust may sell trust property to pay such
amounts. These sales may result in losses to unitholders and the inability
of the trust to meet its investment objective. You could experience a
dilution of your investment if we increase the size of your trust as we sell
units. There is no assurance that your investment will maintain its size or
composition.

* THE TRUST WILL NOT RETURN [$1,010] PER UNIT AT SCHEDULED TRUST TERMINATION
IF A CREDIT EVENT OCCURS WITH RESPECT TO THE REFERENCE ISSUER. If a Credit
Event occurs with respect to the Reference Issuer, the trust is designed to
pay approximately [$202] per unit at scheduled trust termination, resulting
in a significant loss. The trust would also not provide exposure to any
appreciation in the Index in this situation.

* THE TRUSTEE HAS THE POWER TO TERMINATE YOUR TRUST EARLY IN LIMITED CASES AS
DESCRIBED UNDER "UNDERSTANDING YOUR INVESTMENT--HOW YOUR TRUST WORKS--
TERMINATION OF YOUR TRUST". If the trust terminates early, the trust may
suffer losses and be unable to achieve its investment objective. This
could result in a reduction in the value of units and result in a
significant loss to investors even if no credit event occurs with respect
to the Reference Issuer.

Investment Summary 7

* UPON CERTAIN CIRCUMSTANCES LAID OUT IN THE OPTION AGREEMENT, THE OPTIONS
MAY BE TERMINATED EARLY UPON DETERMINATION BY THE OPTION COUNTERPARTY AS
DESCRIBED UNDER "INVESTMENT SUMMARY--PRINCIPAL INVESTMENT STRATEGY--EARLY
OPTION TERMINATION OR LIQUIDATION". An early termination of the Options
may result in the early termination of the trust and/or the trust being
unable to achieve its investment objective and result in a reduction in the
value of your units.

* NO ONE CAN GUARANTEE THAT A LIQUID SECONDARY TRADING MARKET WILL EXIST FOR
THE OPTIONS. The Options will not be listed on any exchange and are not
registered under the Securities Act of 1933. The trust has the right to
terminate the Options with the Option Counterparty prior to the expiration
date. If the trust exercises its right to terminate Options prior to the
expiration date, the Option Counterparty will be obligated to terminate a
portion of the Options for cash equal to an amount payable in connection
with such termination. In addition, in the event any Option is terminated
prior to the expiration date, the Calculation Agent (which is generally the
Option Counterparty) will calculate the amount owed to the trust in
connection with such termination as described above.

* AN INVESTMENT IN THE TRUST IS NOT A DEPOSIT OF ANY BANK AND IS NOT INSURED
OR GUARANTEED BY THE FEDERAL DEPOSIT INSURANCE CORPORATION OR ANY OTHER
GOVERNMENT AGENCY.

* WE DO NOT ACTIVELY MANAGE THE PORTFOLIO. Except in limited circumstances,
the trust will hold, and may continue to buy, the same securities even if
the market value declines.

8 Investment Summary

WHO SHOULD INVEST

You should consider this investment if you want:

* to own securities representing interests in Treasury Obligations and
Options in a single investment.

* the potential for capital appreciation linked to the Index and repayment
at scheduled trust termination of [$1,010] per unit, subject to the credit
of the Reference Issuer, along with income.

You should not consider this investment if you:

* are uncomfortable with the risks of an unmanaged investment in Treasury
Obligations and Options.

* are uncomfortable with exposure to the risks associated with the Options
and the Index.

* are uncomfortable with the potential for a loss of a significant portion
of your investment.

* are seeking unlimited capital appreciation potential or income as a
primary objective.

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ESSENTIAL INFORMATION
---------------------

PUBLIC OFFERING PRICE PER UNIT
AT INCEPTION* [$1,010.00]

PRINCIPAL AMOUNT OF TREASURY
OBLIGATIONS PER UNIT AT INCEPTION* [$1,000.00]

INCEPTION DATE ____________, 2014

MANDATORY TERMINATION DATE ____________, [2020]

ESTIMATED NET ANNUAL INTEREST
INCOME PER UNIT* [$3.36]

ESTIMATED INITIAL DISTRIBUTION
PER UNIT* $_____

DISTRIBUTION DATES 25th day of June
and December
RECORD DATES 10th day of June
and December

INITIAL DISTRIBUTION DATE __________ 25, 201__
INITIAL RECORD DATE __________ 10, 201__

CUSIP NUMBER _________

TICKER SYMBOL ______

MINIMUM INVESTMENT 1 unit

------------------------------------------------------------

<FN>
* As of ____________, 2014 and may vary thereafter.
</FN>

FEES AND EXPENSES

The amounts below are estimates of the direct and indirect expenses that you
may incur based on the initial unit price. Actual expenses may vary.

AS A % AMOUNT
OF $1,000 PER
SALES FEE INVESTED UNIT
------------------------

Maximum sales fee 4.50% [$45.45]
======= =======

ORGANIZATION COSTS [0.38%] $3.80
======= =======

AS A % AMOUNT
ANNUAL OF NET PER
OPERATING EXPENSES ASSETS UNIT
------------------------

Trustee fee & expenses _.__% $____
Supervisory, evaluation
and administration fees _.__ ____
------- -------
Total _.__% $____
======= =======

EXAMPLE

This example helps you compare the cost of this trust with other unit trusts
and mutual funds. In the example we assume that the expenses do not change and
that the trust's annual return is 5%. Your actual returns and expenses will
vary. Based on these assumptions, you would pay these expenses for every
$10,000 you invest in the trust:

1 year $_____
3 years $_____
5 years $_____
[6 years] (approximate life of trust) $_____

These amounts are the same regardless of whether you sell your investment at
the end of a period or continue to hold your investment.

Investment Summary 9

ARMR MLT(SM) SERIES 2014-1, S&P 500(R) PORTFOLIO

(ADVISORS DISCIPLINED TRUST 1237)
PORTFOLIO -- AS OF THE INITIAL DATE OF DEPOSIT, ____________, 2014

PERCENTAGE OF NUMBER MARKET COST OF
DESCRIPTION OF OPTION OPTION AGGREGATE OFFERING OF VALUE PER SECURITIES
OPTIONS(1) COUNTERPARTY EXPIRATION PRICE OPTIONS OPTION(2) TO TRUST(2)
----------------------------------------------------------------------------------------------------------------------------------

OPTIONS -- [0.00%]

--------- ----------
TOTAL OPTIONS ___.__% $________
--------- ----------

PERCENTAGE OF COST OF
NAME OF ISSUER AND TITLE OF AGGREGATE OFFERING PAR SECURITIES
TREASURY OBLIGATION(3) PRICE VALUE TO TRUST(2)
----------------------------------------------------------------------------------------------------------------------------------

TREASURY OBLIGATIONS -- [100.00%]

--------- -----------
TOTAL TREASURY OBLIGATIONS ___.__% $________
--------- -----------

--------- -----------
TOTAL ___.__% $________
========= ===========

<FN>
See "Notes to Portfolio"
</FN>

10 Investment Summary

Notes to Portfolio

(1) The sponsor entered into the Options on ____________, 2014. Payment of
the option premiums of [$1,000] per trust unit is due by ____________, 2020
and the Treasury Obligations are pledged as collateral in order to secure
payment to the Option Counterparty at the expiration or earlier termination
of the Options.

The Options reference the following Reference Issuer:
_________________________

(2) The value of U.S. Treasury obligations is based on the current offering
side evaluation as of the close of the New York Stock Exchange on the
business day prior to the trust's inception date. Advisors Asset
Management, Inc. is the evaluator of the trust. Capelogic, Inc., an
independent pricing service, determined the initial prices of the
securities shown in this prospectus at the close of regular trading on the
New York Stock Exchange or the business day before the date of this
prospectus. The value of the Options is based on the evaluator's good
faith determination of the fair value of the Options at its reasonable
discretion taking into consideration factors, including, but not limited to
(a) the net amount to be paid or received by the trust in connection with
an early termination of Options as determined pursuant to the Option
agreement on the valuation date, (b) current ask prices for the Options as
obtained from investment dealers or brokers who customarily deal in options
comparable to the Options held by the trust and (c) ask prices for
comparable options or securities. The aggregate offering or ask price is
greater than the aggregate bid price of securities, which is the basis on
which redemption prices will be determined for purposes of redemption of
units after the initial offering period. Accounting Standards
Codification 820, "Fair Value Measurements" establishes a framework for
measuring fair value and expands disclosure about fair value measurements
in financial statements for the trust. The framework under the standard is
comprised of a fair value hierarchy, which requires an entity to maximize
the use of observable inputs and minimize the use of unobservable inputs
when measuring fair value. The standard describes three levels of inputs
that may be used to measure fair value:

Level 1: Quoted prices (unadjusted) for identical assets or
liabilities in active markets that the trust has the ability to
access as of the measurement date.

Level 2: Significant observable inputs other than Level 1 prices,
such as quoted prices for similar assets or liabilities, quoted prices
in markets that are not active, and other inputs that are observable
or can be corroborated by observable market data.

Level 3: Significant unobservable inputs that reflect a trust's own
assumptions about the assumptions that market participants would use
in pricing an asset or liability.

The Treasury Obligations are valued as Level 2 securities. The Options
are valued as Level 3 securities. The cost of the securities to the
sponsor and the sponsor's profit or (loss) (which is the difference between
the cost of the securities to the sponsor and the cost of the securities to
the trust) are $__________ and $__________, respectively. The inputs or
methodologies used for valuing securities are not necessarily an indication
of the risk associated with investing those securities. Changes in
valuation techniques may result in transfers in or out of an investment's
assigned level as described above. The following table summarizes the
trust's investments as of ____________, 2014, based on inputs used to value
them:

LEVEL 1 LEVEL 2 LEVEL 3
----------------------------------------------------------------------
Options $ $ $
Treasury Obligations
----------------------------------------------------------------------
Total $ $ $
======================================================================

(3) The Treasury Obligations are represented by contracts to purchase such
securities the performance of which is secured by an irrevocable letter of
credit. Contracts to acquire these securities were entered into on
____________, 2014, and have an expected settlement date of ____________,
2014.

(4) A Treasury Obligation marked with this note was issued at an original
issue discount.

(5) This is a non-income producing security.

Investment Summary 11

-----------------------------
UNDERSTANDING YOUR INVESTMENT
-----------------------------

OPTION EXPIRATION EXAMPLES

The following two tables illustrate the payments on the Options and examples
of how the trust's investment strategy is intended to work.

The tables are hypothetical illustrations of the mathematical principles
underlying the Options and the trust's investment strategy. The tables are not
intended to predict or project the performance of the Options or the trust. The
actual distributions that you receive will vary from these illustrations with
changes in expenses and early termination of Options or defaults by the Option
Counterparty. For an explanation of the Option computations, please refer to
the discussion under "Investment Summary--Principal Investment Strategy".
Negative amounts in the tables below indicate a payment to be made by the trust
and positive amounts indicate a payment to be received by the trust. The
examples apply only to an investment held from the trust's inception date
through the trust's scheduled termination on the mandatory termination date set
forth under "Investment Summary--Essential Information".

The first table shows how the Options and the trust work based on various
hypothetical changes in the Index value assuming no Credit Event with respect to
the Reference Issuer and no default by the Option Counterparty. The second
table shows how the Options and the trust works assuming a Credit Event with
respect to the Reference Issuer and no default by the Option Counterparty. In
the first table, the "Hypothetical Change in Index Value" is the percentage
generated by taking a) the Index Final Value minus the Index Starting Value
divided by b) the Index Starting Value. The "Hypothetical Index Ratio" is the
percentage generated by taking the Index Final Value divided by the Index
Starting Value. In the first table, the "Payment on Options per Unit by Option
Counterparty" reflects the per unit payment owed by the Option Counterparty to
the trust at expiration based on the Options' formula shown under "Investment
Summary--Principal Investment Strategy". In the second table the "Payment on
Options per Unit by Option Counterparty" reflects the per unit payment of [$202]
owed by the Option Counterparty to the trust at expiration based on the terms of
the Options as described under "Investment Summary--Principal Investment
Strategy". In both tables, the "Premium on Options per Unit Owed by Trust"
shown is [$1,000] and will be paid by the trust to the Option Counterparty at
the Option expiration date and will be netted against the amount owed by the
Option Counterparty to the trust. In both tables, the "Maturity Value of
Treasury Obligations per Unit" is based on the amount at inception shown as
Principal amount of Treasury Obligations per unit at inception under "Investment
Summary--Essential Information". In both tables, the "Estimated Net Interest
Income per Unit from Treasury Obligations over Trust's Life" reflects the
"Estimated net annual interest income per unit" shown under "Investment Summary-
-Essential Information" multiplied by the [6] year term of the trust, which
actual amount may vary based on the trust's expenses and other factors described
under "Understanding Your Investment--Distributions--Estimated Distributions".
The "Hypothetical Total Amount for Trust per Unit" is the sum of the preceding
four columns.

All figures in the tables assume that the Options are held until their
scheduled expiration and units are held until the trust's mandatory termination
date. Early terminations of the Options will result in the trust receiving or
making net payments on the Options as determined by the Calculation Agent (which
is generally the Option Counterparty). All amounts in the tables and the
examples below are rounded to the nearest dollar for ease of analysis.

12 Understanding Your Investment

--------------------------------------------------------------------------------------------------------------------------

HOW THE TRUST WORKS: NO CREDIT EVENT ON REFERENCE ISSUER
HYPOTHETICAL PAYMENTS ON THE OPTIONS AND TREASURY OBLIGATIONS ASSUMING NO CREDIT EVENT
WITH RESPECT TO THE REFERENCE ISSUER (PAYMENTS SHOWN PER TRUST UNIT)

ESTIMATED
HYPOTHETICAL PAYMENT ON PREMIUM ON MATURITY NET INTEREST
INDEX RATIO OPTIONS OPTIONS VALUE OF INCOME PER UNIT HYPOTHETICAL
HYPOTHETICAL (INDEX FINAL PER UNIT PER UNIT TREASURY FROM TREASURY TOTAL AMOUNT
CHANGE IN VALUE / INDEX BY OPTION OWED OBLIGATIONS OBLIGATIONS OVER FOR TRUST
INDEX VALUE STARTING VALUE) COUNTERPARTY BY TRUST PER UNIT TRUST'S LIFE PER UNIT
--------------------------------------------------------------------------------------------------------------------------

100% 200% [$1,414] + [-$1,000] + [$1,000] + [$20] = [$1,434]
90% 190% [$1,414] + [-$1,000] + [$1,000] + [$20] = [$1,434]
80% 180% [$1,414] + [-$1,000] + [$1,000] + [$20] = [$1,434]
70% 170% [$1,414] + [-$1,000] + [$1,000] + [$20] = [$1,434]
60% 160% [$1,414] + [-$1,000] + [$1,000] + [$20] = [$1,434]
50% 150% [$1,414] + [-$1,000] + [$1,000] + [$20] = [$1,434]
40% 140% [$1,394] + [-$1,000] + [$1,000] + [$20] = [$1,414]
30% 130% [$1,293] + [-$1,000] + [$1,000] + [$20] = [$1,313]
20% 120% [$1,192] + [-$1,000] + [$1,000] + [$20] = [$1,212]
10% 110% [$1,091] + [-$1,000] + [$1,000] + [$20] = [$1,111]
0% 100% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-10% 90% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-20% 80% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-30% 70% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-40% 60% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-50% 50% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-60% 40% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-70% 30% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-80% 20% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-90% 10% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]
-100% 0% [$1,010] + [-$1,000] + [$1,000] + [$20] = [$1,030]

--------------------------------------------------------------------------------------------------------------------------

------------------------------------------------------------------------------------------------------------

HOW THE TRUST WORKS: CREDIT EVENT ON REFERENCE ISSUER
HYPOTHETICAL PAYMENTS ON THE OPTIONS AND TREASURY OBLIGATIONS IF THERE IS A CREDIT EVENT
WITH RESPECT TO THE REFERENCE ISSUER (PAYMENTS SHOWN PER TRUST UNIT)

ESTIMATED
PAYMENT ON PREMIUM ON MATURITY NET INTEREST
OPTIONS OPTIONS VALUE OF INCOME PER UNIT HYPOTHETICAL
PER UNIT PER UNIT TREASURY FROM TREASURY TOTAL AMOUNT
BY OPTION OWED OBLIGATIONS OBLIGATIONS OVER FOR TRUST
COUNTERPARTY BY TRUST PER UNIT TRUST'S LIFE PER UNIT
------------------------------------------------------------------------------------------------------------

[$202] + [-$1,000] + [$1,000] + [$20] = [$222]

------------------------------------------------------------------------------------------------------------

Understanding Your Investment 13

Example--Hypothetical Index Ratio is 150% at Expiration
-------------------------------------------------------------------------------

The following provides examples of how the Options and the Trust work where
the Hypothetical Index Ratio is 150% in the table above (i.e., where the Index
has appreciated by 50%).

If we assume that no Credit Event has occurred with respect to the Reference
Issuer during the life of the trust the following payments are intended to be
made:

* Approximately [$20] per unit in estimated net interest income per unit
from Treasury Obligations over the trust's life.

* [$1,000] per unit at the trust's scheduled termination from the maturity
proceeds from the Treasury Obligations (i.e., the par value of the Treasury
Obligations).

* [$414] per unit at the trust's scheduled termination from the net payment
to the trust by the Option Counterparty, calculated as follows: [$1,010] X
([150%] - [2%], subject to a minimum of [100%] and a maximum of [140%]) =
[$1,414] per unit. Because the trust would be required to pay a premium on
the Option of [$1,000] per unit, the net payment to the trust by the Option
Counterparty would be [$414] per unit as shown in the table above.

In this example, the total hypothetical amount returned per unit over the
trust's life assuming no Credit Event with respect to the Reference Issuer is
approximately [$1,434] as shown in the table above ([$20]+[$1,000]+[$1,414]-
[$1,000]).

If we assume that a Credit Event has occurred with respect to the Reference
Issuer during the life of the trust the following payments are intended to be
made:

* Approximately [$20] per unit in estimated net interest income per unit
from Treasury Obligations over the trust's life.

* [$202] per unit at the trust's scheduled termination consisting of the
maturity proceeds from the Treasury Obligations less the net payment by the
trust to the Option Counterparty under the Options. Because a Credit Event
occurred with respect to the Reference Issuer, the Option would provide for
a payment by the Option Counterparty to the trust equal to [$202] per unit.
Because the trust would be required to pay a premium on the Option of
[$1,000] per unit, the net payment to the Option Counterparty by the trust
would be [$798] per unit as shown in the table above, paid from the
maturity proceeds from the Treasury Obligations of [$1,000] per unit.

In this example, the total hypothetical amount returned per unit over the
trust's life assuming a Credit Event has occurred with respect to the Reference
Issuer is approximately [$222] as shown in the table above
([$20]+[$1,000]+[$202]-[$1,000]).

Example--Hypothetical Index Ratio is 110% at Expiration
-------------------------------------------------------------------------------

The following provides examples of how the Options and the Trust work where
the Hypothetical Index Ratio is 110% in the table above (i.e., where the Index
has appreciated by 10%).

14 Understanding Your Investment

If we assume that no Credit Event has occurred with respect to the Reference
Issuer during the life of the trust the following payments are intended to be
made:

* Approximately [$20] per unit in estimated net interest income per unit
from Treasury Obligations over the trust's life.

* [$1,000] per unit at the trust's scheduled termination from the maturity
proceeds from the Treasury Obligations (i.e., the par value of the Treasury
Obligations).

* [$91] per unit at the trust's scheduled termination from the net payment
to the trust by the Option Counterparty, calculated as follows: [$1,010] X
([110%] - [2%], subject to a minimum of [100%] and a maximum of [140%]) =
[$1,091] per unit. Because the trust would be required to pay a premium on
the Option of [$1,000] per unit, the net payment to the trust by the Option
Counterparty would be [$91] per unit as shown in the table above.

In this example, the total hypothetical amount returned per unit over the
trust's life assuming no Credit Event with respect to the Reference Issuer is
approximately [$1,111] as shown in the table above ([$20]+[$1,000]+[$1,091]-
[$1,000]).

If we assume that a Credit Event has occurred with respect to the Reference
Issuer during the life of the trust the following payments are intended to be
made:

* Approximately [$20] per unit in estimated net interest income per unit
from Treasury Obligations over the trust's life.

Example--Hypothetical Index Ratio is 100% at Expiration
-------------------------------------------------------------------------------

The following provides examples of how the Options and the Trust work where
the Hypothetical Index Ratio is 100% in the table above (i.e., where the Index
Final Value is at the same level as the closing level on [____________, 2014].

If we assume that no Credit Event has occurred with respect to the Reference
Issuer during the life of the trust the following payments are intended to be
made:

* Approximately [$20] per unit in estimated net interest income per unit
from Treasury Obligations over the trust's life.

Understanding Your Investment 15

* [$1,000] per unit at the trust's scheduled termination from the maturity
proceeds from the Treasury Obligations (i.e., the par value of the Treasury
Obligations).

* [$10] per unit at the trust's scheduled termination from the net payment
to the trust by the Option Counterparty, calculated as follows: [$1,010] X
([100%] - [2%], subject to a minimum of [100%] and a maximum of [140%]) =
[$1,010] per unit. Because the trust would be required to pay a premium on
the Option of [$1,000] per unit, the net payment to the trust by the Option
Counterparty would be [$10] per unit as shown in the table above.

In this example, the total hypothetical amount returned per unit over the
trust's life assuming no Credit Event with respect to the Reference Issuer is
approximately [$1,030] as shown in the table above ([$20]+[$1,000]+[$1,010]-
[$1,000]).

If we assume that a Credit Event has occurred with respect to the Reference
Issuer during the life of the trust the following payments are intended to be
made:

* Approximately [$20] per unit in estimated net interest income per unit
from Treasury Obligations over the trust's life.

Example--Hypothetical Index Ratio is 70% at Expiration
-------------------------------------------------------------------------------

The following provides examples of how the Options and the Trust work where
the Hypothetical Index Ratio is 70% in the table above (i.e., where the Index
has depreciated by 30%).

If we assume that no Credit Event has occurred with respect to the Reference
Issuer during the life of the trust the following payments are intended to be
made:

* Approximately [$20] per unit in estimated net interest income per unit
from Treasury Obligations over the trust's life.

* [$1,000] per unit at the trust's scheduled termination from the maturity
proceeds from the Treasury Obligations (i.e., the par value of the Treasury
Obligations).

* [$10] per unit at the trust's scheduled termination from the net payment
to the

16 Understanding Your Investment

trust by the Option Counterparty, calculated as follows: [$1,010] X
([70%] - [2%], subject to a minimum of [100%] and a maximum of [140%]) =
[$1,010] per unit. Because the trust would be required to pay a premium on
the Option of [$1,000] per unit, the net payment to the trust by the Option
Counterparty would be [$0] per unit as shown in the table above.

If we assume that a Credit Event has occurred with respect to the Reference
Issuer during the life of the trust the following payments are intended to be
made:

* Approximately [$20] per unit in estimated net interest income per unit
from Treasury Obligations over the trust's life.

The tables above are provided for illustrative purposes only and are
hypothetical. The tables do not purport to be representative of every possible
scenario concerning the Index Ratio. No one can predict the Index Ratio or
whether a Credit Event will occur with respect to the Reference Issuer. The
assumptions made in connection with the examples may not reflect actual events.
You should not take these examples as an indication or assurance of the expected
performance of the Index, the Reference Issuer, the Options or the return on the
trust units.

These examples do not attempt to present any projection of actual trust
performance. These examples are merely intended to illustrate the operation of
the Options at the scheduled expiration and the amount per unit that the trust
would receive or pay in certain situations at the scheduled expiration of the
Options.

These examples assume that the units were purchased at the trust's inception
and held until the trust's scheduled termination date and that the Options are
held by the trust to expiration on [_________, 2020], that all Options are paid
by the Option Counterparty according to their terms (i.e. no default and no
early termination). These examples also assume that the Treasury Obligations
are held until their scheduled maturities.

Understanding Your Investment 17

These examples do not show the past performance of the Index, Reference
Issuer, Options or any investment. These examples are for illustrative purposes
only and are not intended to be indicative of future results of the Index,
Reference Issuer, the Options or the trust's units. The examples only
illustrate payments related to the Options at the scheduled Option expiration
and hypothetical performance of the trust's assets at the scheduled termination
date. The actual overall performance of the trust will vary with fluctuations
in the value of the Options and Treasury Obligations during the trust's life,
changes in trust expenses and liquidations of Options and Treasury Obligations
during the trust's life, among other things.

If the Option Counterparty becomes insolvent, the trust may suffer losses or
be unable to achieve its investment objective and it may result in a reduction
in the value of your units and result in a loss. If the Index Final Value is
greater than the Index Starting Value (i.e. an increase in the value of the
Index) and the Option Counterparty becomes insolvent, you should not expect to
receive any capital appreciation linked to the performance of the Index. If the
Option Counterparty becomes insolvent and the trust is owed a net payment on the
Options from the Option Counterparty, the trust may not be able to recover any
such amounts owed. If the Option Counterparty becomes insolvent and the trust
owes a net payment on the Options to the Option Counterparty, the Options may be
terminated early and the trust may be required to make this payment prior to the
Options' scheduled expiration date. This could result in a loss to the trust on
the Options prior to the Options' scheduled expiration date where a loss may not
have otherwise been experienced if the Options were held to their scheduled
expiration date.

HOW TO BUY UNITS

You can buy units of a trust on any business day the New York Stock Exchange
is open by contacting your financial professional. Unit prices are available
daily on the Internet at WWW.AAM.US.COM. The public offering price of units
includes:

* the net asset value per unit plus

* cash to pay organization costs plus

* the sales fee plus

* accrued interest, if any.

The "net asset value per unit" is the value of the securities, cash and other
assets in a trust reduced by the liabilities of a trust divided by the total
units outstanding. We often refer to the public offering price of units as the
"offer price" or "purchase price." The offer price will be effective for all
orders received prior to the close of regular trading on the New York Stock
Exchange (normally 4:00 p.m. Eastern time). If we receive your order prior to
the close of regular trading on the New York Stock Exchange or authorized
financial professionals receive your order prior to that time and properly
transmit the order to us by the time that we designate, then you will receive
the price computed on the date of receipt. If we receive your order after the
close of regular trading on the New York Stock Exchange, if authorized financial
professionals receive your order after that time or if orders are received by
such persons and are not transmitted to us by the time that we designate, then
you will receive the price computed on the date of the next determined offer
price provided that your order is received in a timely manner on that date. It
is the responsibility of the authorized financial professional to transmit the
orders that they receive to us in a timely manner. Certain broker-dealers

18 Understanding Your Investment

may charge a transaction or other fee for processing unit purchase orders.

ORGANIZATION COSTS. During the initial offering period, part of the value of
the units represents an amount of cash deposited to pay the costs of creating
your trust. These costs include the costs of preparing the registration
statement and legal documents, federal and state registration fees, the initial
fees and expenses of the trustee and the initial audit. Your trust will
reimburse us for these costs at the end of the initial offering period or after
six months, if earlier. The value of your units will decline when the trust
pays these costs.

ACCRUED INTEREST. Accrued interest represents unpaid interest on a Treasury
Obligation from the last day it paid interest. Accrued interest on the trust
units consists of two elements. The first element arises as a result of accrued
interest which is the accumulation of unpaid interest on Treasury Obligation in
the trust from the last day on which interest was paid on the Treasury
Obligations. Interest on the Treasury Obligation is generally paid semi-
annually, although the trust accrues such interest daily. Because your trust
always has an amount of interest earned but not yet collected, the public
offering price of units will have added to it the proportionate share of accrued
interest to the date of settlement. The second element of accrued interest
arises because of the structure of the trust's interest account. The trustee
has no cash for distribution to unitholders until it receives interest payments
on the Treasury Obligations in the trust and may be required to advance its own
funds to make trust interest distributions. As a result, interest account
balances are established to limit the need for the trustee to advance funds in
connection with such interest distributions. If you sell or redeem your units
you will be entitled to receive your proportionate share of the accrued interest
from the purchaser of your units.

VALUE OF THE SECURITIES. We determine the value of the securities as of the
close of regular trading on the New York Stock Exchange on each day that
exchange is open. We determine the value of the Options in the trust's
portfolio as of the close of regular trading on the New York Stock Exchange on
each day that exchange is open. We determine the Options' values based on our
good faith determination of the Option's fair value. We will determine the
value of the Options during the initial offering period (anticipated to be only
one day, the initial date of deposit) based on our good faith determination of
the fair value of the Options at our reasonable discretion taking into
consideration factors, including, but not limited to, (a) the net amount to be
paid to or received by the trust in connection with an early termination of
Options as determined pursuant to the Option agreement by the Calculation Agent
(which is generally the Option Counterparty), (b) current ask prices for the
Options as obtained from investment dealers or brokers who customarily deal in
options comparable to the Options held by the trust and (c) ask prices for
comparable options or securities.

We determine the value of the Treasury Obligations based on our good faith
determination of the Treasury Obligations' fair value. We generally determine
the value of the Treasury Obligations during the initial offering period based
on the aggregate offering side evaluations of the Treasury Obligations
determined (a) on the basis of current offering prices of the Treasury
Obligations, (b) if offering prices are not available for any particular
Treasury Obligation, on the basis of current offering prices for comparable
securities, (c) by determining the value of the Treasury Obligations on the
offer side of the

Understanding Your Investment 19

market by appraisal, or (d) by any combination of the above.

After the initial offering period ends, we generally determine the value of
the Treasury Obligations and Options as described in the preceding paragraphs
based on the bid side evaluations rather than the offering/ask side evaluations.
The offering/ask side price generally represents the price at which dealers,
market-makers or investors in the market are willing to sell a security and the
bid side evaluation generally represents the price that dealers, market-makers
or investors in the market are willing to pay to buy a security. The bid side
evaluation is lower than the offering/ask side evaluation. As a result of this
pricing method, unitholders should expect a decrease in the net asset value per
unit on the day following the end of the initial offering period equal to the
difference between the current offering side evaluation and bid side evaluation
of the Treasury Obligations and Options.

Capelogic, Inc., an independent pricing service, determined the initial
prices of the securities shown under "Portfolio" in this prospectus as described
above at the close of regular trading on the New York Stock Exchange on the
business day before the date of this prospectus. On the first day we sell units
we will compute the unit price as of the close of regular trading on the New
York Stock Exchange or the time the registration statement filed with the
Securities and Exchange Commission becomes effective, if later.

SALES FEE. You pay a fee in connection with purchasing units. We refer to
this fee as the "sales fee." You pay the sales fee at the time you buy units.
The maximum sales fee equals 4.50% of the public offering price per unit at the
time of purchase.

MINIMUM PURCHASE. The minimum amount you can purchase of the trust appears
on page 9 under "Essential Information", but such amounts may vary depending on
your selling firm.

RETIREMENT ACCOUNTS. The portfolio may be suitable for purchase in tax-
advantaged retirement accounts. You should contact your financial professional
about the accounts offered and any additional fees imposed.

HOW TO SELL YOUR UNITS

You can sell or redeem your units on any business day the New York Stock
Exchange is open by contacting your financial professional. Unit prices are
available daily on the Internet at WWW.AAM.US.COM or through your financial
professional. The sale and redemption price of units is equal to the net asset
value per unit, provided that you will not pay any remaining organization costs
if you sell or redeem units during the initial offering period. The sale and
redemption price is sometimes referred to as the "liquidation price". Certain
broker-dealers may charge a transaction or other fee for processing unit
redemption or sale requests.

SELLING UNITS. We may maintain a secondary market for units. This means
that if you want to sell your units, we may buy them at the current net asset
value, provided that you will not pay any remaining organization costs if you
sell units during the initial offering period. We may then resell the units to
other investors at the public offering price or redeem them for the redemption
price. Our secondary market repurchase price is the same as the redemption
price. Certain broker-dealers might also maintain a secondary market in units.
You should contact your financial professional for current repurchase prices to
determine the best price available. We may discontinue our

20 Understanding Your Investment

secondary market at any time without notice. Even if we do not make a market,
you will be able to redeem your units with the trustee on any business day for
the current redemption price.

REDEEMING UNITS. You may also redeem your units directly with the trustee,
The Bank of New York Mellon, on any day the New York Stock Exchange is open.
The redemption price that you will receive for units is equal to the net asset
value per unit, provided that you will not pay any remaining organization costs
if you redeem units during the initial offering period. You will receive the
net asset value for a particular day if the trustee receives your completed
redemption request prior to the close of regular trading on the New York Stock
Exchange. Redemption requests received by authorized financial professionals
prior to the close of regular trading on the New York Stock Exchange that are
properly transmitted to the trustee by the time designated by the trustee, are
priced based on the date of receipt. Redemption requests received by the
trustee after the close of regular trading on the New York Stock Exchange,
redemption requests received by authorized financial professionals after that
time or redemption requests received by such persons that are not transmitted to
the trustee until after the time designated by the trustee, are priced based on
the date of the next determined redemption price provided they are received in a
timely manner by the trustee on such date. It is the responsibility of
authorized financial professionals to transmit redemption requests received by
them to the trustee so they will be received in a timely manner. If your
request is not received in a timely manner or is incomplete in any way, you will
receive the next net asset value computed after the trustee receives your
completed request.

If you redeem your units, the trustee will generally send you a payment for
your units no later than seven days after it receives all necessary
documentation (this will usually only take three business days). The only time
the trustee can delay your payment is if the New York Stock Exchange is closed
(other than weekends or holidays), the Securities and Exchange Commission
determines that trading on that exchange is restricted or an emergency exists
making sale or evaluation of the securities not reasonably practicable, and for
any other period that the Securities and Exchange Commission permits.

EXCHANGE OPTION. You may be able to exchange your units for units of our
other unit trusts at a reduced sales fee. You can contact your financial
professional for more information about trusts currently available for
exchanges. Before you exchange units, you should read the prospectus carefully
and understand the risks and fees. You should then discuss this option with
your financial professional to determine whether your investment goals have
changed, whether current trusts suit you and to discuss tax consequences. We
may discontinue this option upon sixty days notice.

DISTRIBUTIONS

DISTRIBUTIONS. Your trust generally pays interest from its net investment
income along with any available principal paid on the securities on the
distribution date to unitholders of record on the preceding record date,
provided that the total cash held for distribution equals at least 0.1% of the
trust's net asset value as determined under the trust agreement. The record and
distribution dates are shown under "Essential Information" in the "Investment
Summary" section of this prospectus. In some cases, your trust might pay a
special distribution if it holds an excessive amount of cash pending
distribution. The amount of your distributions will vary from time to time as

Understanding Your Investment 21

interest and principal payments change or trust expenses change.

Interest received by your trust, including that part of the proceeds of any
disposition of securities which represents accrued interest, is credited by the
trustee to your trust's "interest account". Other receipts are credited to the
"principal account". After deduction of amounts sufficient to reimburse the
trustee, without interest, for any amounts advanced and paid to the sponsor as
the unitholder of record as of the first settlement date, interest received will
be distributed on each distribution date to unitholders of record as of the
preceding record date. All distributions will be net of estimated expenses.
Funds in the principal account will be distributed on each distribution date to
unitholders of record as of the preceding record date provided that the amount
available for distribution therein shall equal at least $1.00 per unit.
Investors who purchase units between a record date and a distribution date will
receive their first distribution on the second distribution date after the
purchase.

ESTIMATED DISTRIBUTIONS. The estimated net annual interest income per unit
as of the close of business the day before your trust's inception date is shown
under "Essential Information" in the "Investment Summary" section of this
prospectus. We base these amounts on the estimated cash flows of the bonds per
unit based on the stated interest rate on the bonds reduced by the estimated
trust fees and expenses. These amounts assume no changes in trust expenses, no
changes in current interest rates, no default or any calls, sales, prepayments
or other liquidations of the bonds prior to the stated maturity date of the
bonds. The actual distributions that you receive will vary from these estimates
with changes in expenses, interest rates and maturity, call, default or sale of
bonds.

In order to acquire the Treasury Obligations, it may be necessary for the
sponsor or trustee to pay amounts covering accrued interest on the bonds which
exceed the amounts which will be made available through cash furnished by the
sponsor on the trust's inception date. This cash may exceed the interest which
would accrue to the first settlement date. The trustee has agreed to pay for any
amounts necessary to cover any excess and will be reimbursed when funds become
available from interest payments on the related bonds.

REPORTS. The trustee or your financial professional will make available to
you a statement showing income and other receipts of your trust for each
distribution. Each year the trustee or your financial professional will also
provide an annual report on your trust's activity and certain tax information.
You can request copies of security evaluations to enable you to complete your
tax forms and audited financial statements for your trust, if available.

INVESTMENT RISKS

All investments involve risk. This section describes the main risks that can
impact the value of the securities in your portfolio. You should understand
these risks before you invest. If the value of the securities falls, the value
of your units will also fall. We cannot guarantee that your trust will achieve
its objective or that your investment return will be positive over any period.

22 Understanding Your Investment

a security. While the Options are related to the performance of the Index, the
return on the Options at expiration depends on the Index level on that date and
whether a Credit Event has occurred with respect to the Reference Issuer prior
to expiration. The terms of the Options provide for Options liquidated prior to
their expiration to have amounts owed between the trust and the Option
Counterparty to be determined by the Calculation Agent (who is generally the
Option Counterparty) in good faith and using commercially reasonable procedures.
The scheduled Option expiration date is [____________, 2020]. Even though we
supervise your portfolio, you should remember that we do not manage your
portfolio. Your trust will not sell a security solely because the market value
falls as is possible in a managed fund. The trust does not guarantee any return
of principal.

INTEREST RATE RISK is the risk that the value of securities will fall if
interest rates increase. The Treasury Obligations typically fall in value when
interest rates rise and rise in value when interest rates fall. Securities with
longer periods before maturity are often more sensitive to interest rate
changes.

CREDIT RISK is the risk that a security's issuer or counterparty is unable to
meet its obligation on the security. The trust's ability to achieve its
investment objective will depend upon the ability of the Option Counterparty to
meet its obligations and the ability of the Reference Issuer to avoid a Credit
Event. If the Reference Issuer faces a Credit Event the trust will be unable to
achieve its objective. An option involves a risk of non-payment by the Option
Counterparty as a result of the insolvency of the Option Counterparty or other
factors, including political or economic events. If the Option Counterparty
defaults on any payment that becomes due to the trust, to the extent not covered
by posted collateral, if any, the trust may suffer losses, be unable to achieve
its investment objective and it may result in a reduction in the value of your
units. If the Index Final Value is greater than the Index Starting Value (i.e.
an increase in the value of the Index) and the Option Counterparty becomes
insolvent, you should not expect to receive any capital appreciation linked to
the performance of the Index. If the Option Counterparty becomes insolvent and
the trust is owed a net payment on the Options from the Option Counterparty, the
trust may not be able to recover any such amounts owed. If the Option
Counterparty becomes insolvent and the trust owes a net payment on the Options
to the Option Counterparty, the Options may be terminated early and the trust
may be required to make this payment prior to the Options' scheduled expiration
date. This could result in a loss to the trust on the Options prior to the
Options' scheduled expiration date where a loss may not have otherwise been
experienced if the Options were held to their scheduled expiration date.

EQUITY RISK. The Options represent indirect positions in the Index and are
subject to changes in value as the Index rises or falls. The value of the
Options may be adversely affected by various factors, including factors
affecting the Index and the value of the underlying securities. The Index
consists primarily of large-capitalization stocks, the returns of which may vary
from those of the overall U.S. stock market. The value of the Index will
fluctuate over time based on changes in general economic conditions,
expectations for future economic growth and corporate profits, interest rates,
the supply and demand for large-capitalization stocks in the U.S. and other
factors. Although common stocks have historically generated higher average
returns than fixed-income securities over the long term, common stocks also have
experienced significantly more volatile

Understanding Your Investment 23

returns. Common stocks are structurally subordinated to preferred stocks, bonds
and other debt instruments in a company's capital structure, and represent a
residual claim on the issuer's assets that have no value unless such assets are
sufficient to cover all other claims.

INDEX RISK. The policies of the Index sponsor and any changes affecting the
Index or the Index constituents could affect the market value of the trust and
its units. The policies of the Index sponsor concerning the calculation of the
levels of the Index or additions, deletions or substitutions of the Index
constituents and the manner in which changes affecting such Index constituents
or their issuers, such as stock dividends, reorganizations or mergers, are
reflected in the level of the Index, could affect the levels of the Index and,
therefore, the amount payable in respect of units of the trust on the
termination date and the market value of the trust and its units prior to the
termination date. The market value of the trust and its units could also be
affected if the Index sponsor changes these policies, for example, by changing
the manner in which it calculates the level of the Index, or if the Index
sponsor discontinues or suspends calculation or publication of the level of the
Index, in which case it may become difficult to determine the market value of
the trust and its units. Unitholders will have no rights against the Index
sponsor, even if the Index sponsor decides to suspend the calculation of the
Index and this suspension adversely impacts the amount unitholders receive at
termination.

U.S. TREASURY OBLIGATIONS. U.S. Treasury obligations are direct obligations
of the United States which are backed by the full faith and credit of the United
States. The value of the Treasury Obligations will be adversely affected by
decreases in bond prices and increases in interest rates. Certain Treasury
Obligations may have been purchased on the trust's inception date at prices of
less than their par value at maturity, indicating a market discount. Certain
Treasury Obligations may have been purchased on the trust's inception date at
prices greater than their par value at maturity, indicating a market premium.
The coupon interest rate of Treasury Obligations purchased at a market discount
was lower than current market interest rates of newly issued bonds of comparable
rating and type and the coupon interest rate of Treasury Obligations purchased
at a market premium was higher than current market interest rates of newly
issued bonds of comparable rating and type. Generally, the value of bonds
purchased at a market discount will increase in value faster than bonds
purchased at a market premium if interest rates decrease. Conversely, if
interest rates increase, the value of bonds purchased at a market discount will
decrease faster than bonds purchased at a market premium. A portion of the
Treasury Obligations held by the trust will be segregated by the trustee as
collateral in order to secure the trust's obligation to pay the Option premium.

OPTION ADJUSTMENT. The Options' formula has a negative adjustment of [2%]
with respect to the Index. As a result, the amount realized on the Options will
generally be less than any appreciation of the Index.

CAPPED UPSIDE. The Option payment related to the Index and, as a result, the
trust return is subject to a capped upside. If the Index Final Value is more
than [42]% over the Index Starting Value, the amount realized on the Options
will be capped at [40%] and will be less than the performance of the Index.

THE OPTIONS. The return on the Options at expiration depends on the
performance of the Index and whether a Credit Event occurs with

24 Understanding Your Investment

respect to the Reference Issuer of the Reference Obligation prior to expiration.
The terms of the Options provide for Options liquidated prior to their
expiration to have amounts owed between the trust and the Option Counterparty to
be determined by the Calculation Agent (which is generally the Option
Counterparty) in good faith and using commercially reasonable procedures. The
scheduled Option expiration date is [____________, 2020]. In addition,
litigation regarding the Option Counterparty or of the industries represented by
the Option Counterparty may negatively impact the values of the Options.

Disruptions or suspensions of trading in the securities markets or the Index
may make valuation of the Options difficult. If such a disruption occurs at or
near the expiration date of the Options, there may be a delay in calculation of
the Option payment at expiration of the Options and/or a delay in any payment by
the Option Counterparty of as many as eight days. If a postponement occurs, the
calculation agent for the Options would typically determine the Option payment,
price or other amount with respect to that valuation date on the first
succeeding business day on which no disruption event occurs or is continuing.
The Options may limit the amount of time that such a postponement may continue.
If a disruption event occurs on the last possible date for calculating the
Option payment, the calculation agent may make a good faith estimate of the
Option payment that would have prevailed in the absence of the market
disruption. Any market disruption or delay in valuation as a result of any
disruption could have an adverse affect on the trust and the value of units.

The trust has the right to terminate all or a portion of the Options prior to
the expiration date by tendering such Options to the Option Counterparty. This
might happen to satisfy unit redemptions, pay trust expenses or in certain other
limited circumstances to protect the trust as described in this prospectus.
Upon certain circumstances laid in at the option agreement, the Options may upon
determination by the Option Counterparty be terminated early. This may include,
but is not limited to the trust terminating early or the Option Counterparty
being unable to hedge the risks associated with the Options or having the cost
of such hedging increase materially. This determination as to whether to
terminate the Options early will be made by the Option Counterparty at its sole
discretion.

The Option Counterparty or an affiliate thereof will generally act as
Calculation Agent for the Options. Upon a default by the Option Counterparty,
the trust's sponsor will become the Calculation Agent. The duties of the
Calculation Agent include making determinations that affect the Options, such as
determining the returns used to determine the final payment by the Options,
calculating the value of the Options if Options are tendered for early
termination, determining adjustments with respect to the Options whether to
postpone payment due to a market or or other event. The exercise of these
duties could adversely affect the value of the Options and may present a
conflict of interest between the Calculation Agent and the trust. In addition,
the Option Counterparty or an affiliate determines the value at which the trust
may terminate the Options. The exercise of this duty by the Option Counterparty
or its affiliate could adversely affect the value of the Options and presents a
conflict of interest between the Option Counterparty and the trust. Neither the
sponsor nor the trustee are affiliated with the Option Counterparty.

EARLY TRUST TERMINATION. The trustee has the power to terminate your trust
early in limited

Understanding Your Investment 25

cases as described under "Understanding Your Investment--How Your Trust Works--
Termination of Your Trust". If the trust terminates early, the trust may suffer
losses and be unable to achieve its investment objective. This could result in
a reduction in the value of units and result in a significant loss to investors
even if no credit event occurs with respect to the Reference Issuer.

EARLY OPTION TERMINATION BY OPTION COUNTERPARTY. Upon certain circumstances
laid out in the option agreement, the Options may be terminated early upon
determination by the Option Counterparty as described under "Investment Summary-
-Principal Investment Strategy--Early Option Termination or Liquidation". An
early termination of the Options may result in the early termination of the
trust and/or the trust being unable to achieve its investment objective and
result in a reduction in the value of your units.

PAYMENT AT SCHEDULED TERMINATION. The trust is designed to provide an amount
per unit at scheduled termination of [$1,010] plus a potential amount linked to
the Index performance. The trust will not return [$1,010] per unit at scheduled
trust termination in certain circumstances. These circumstances may include,
but are not necessarily limited to, if a Credit Event occurs with respect to the
Reference Issuer, the Options are terminated early by the Option Counterparty or
the trust, the trust terminates early, units of the trust are redeemed early,
the Option Counterparty defaults on its obligations, or the trust disposes of
Options or Treasury Obligations for any reason, including to pay unit
redemptions or trust expenses, due to adverse credit factors affecting the
Option Counterparty or due to adverse tax law changes affecting treatment of the
Options. If trust operating expenses exceed the interest income received by the
trust on the Treasury Obligations, the trustee would need to sell Options and/or
Treasury Obligations to pay trust expenses and the trust would not achieve its
objectives.

LIQUIDITY RISK is the risk that the value of a security will fall if trading
activity in the security is limited or absent. No one can guarantee that a
liquid trading market will exist for any security because these securities
generally trade in the over-the-counter market (they are not listed on a
securities exchange). In particular, there may not be any secondary market for
the Options. Upon issuance, the Options will not have an established trading
market and were not registered by the issuer under the Securities Act of 1933.
This could adversely affect the trust and the value of units.

SALE OF TRUST PROPERTY TO PAY TRUST EXPENSES. Distributions of interest from
the Treasury Obligations may be insufficient to meet any or all expenses of the
trust. If the cash balances in the income and capital accounts are insufficient
to provide for expenses and other amounts payable by the trust, the trust may
sell trust property to pay such amounts. These sales may result in losses to
unitholders and the inability of the trust to meet its investment objective.

FINANCIAL SERVICES RISK. The trust is exposed to risks associated with the
Option Counterparty which is a company in the financial services industry.
Negative developments in the financial services industry may affect the value of
your investment more than would be the case in a more diversified investment.

__________ RISK. The trust is exposed to risks associated with the Reference
Issuer which is a company in the __________ industry. Negative developments in
the _________ industry may affect the value of your investment more

26 Understanding Your Investment

than would be the case in a more diversified investment.

DIVIDEND AND VOTING RISK. Unitholders will not have control, voting rights
or rights to receive cash dividends or other distributions or other rights that
holders of a direct investment in the Index constituents would normally have.
Because of this and other factors, the return on the units will not be the same
as the return you would receive if you were to purchase those stocks and hold
them for a period equal to the term of the trust.

LEGISLATION OR LITIGATION RISK. Tax legislation proposed by the President or
Congress, tax regulations proposed by the U.S. Treasury or positions taken by
the Internal Revenue Service could affect the value of the trust by changing the
taxation or tax characterizations of the portfolio securities, or income paid by
or related to such securities. Congress has considered such proposals in the
past and may do so in the future. Various legislative initiatives will be
proposed from time to time in the United States and abroad which may have a
negative impact on certain of the issuers represented in the trust. In
addition, litigation regarding any of the issuers of the securities or of the
industries represented by these issuers may negatively impact the share prices
of these securities. No one can predict whether any legislation will be
proposed, adopted or amended and no one can predict the impact that any other
legislation might have on the trust or its portfolio securities.

NO FDIC GUARANTEE. An investment in the trust is not a deposit of any bank
and is not insured or guaranteed by the Federal Deposit Insurance Corporation or
any other government agency.

HOW YOUR TRUST WORKS

YOUR TRUST. Your trust is a unit investment trust registered under the
Investment Company Act of 1940. We created the trust under a trust agreement
between Advisors Asset Management, Inc. (as depositor/sponsor, evaluator and
supervisor) and The Bank of New York Mellon (as trustee). To create your trust,
we caused securities to be deposited with the trustee (or contracts to purchase
securities along with an irrevocable letter of credit or other consideration to
pay for the securities). In exchange, the trustee delivered units of your trust
to us. Each unit represents an undivided interest in the assets of your trust.
These units remain outstanding until redeemed or until your trust terminates.
At the close of the New York Stock Exchange on the trust's inception date, the
number of units may be adjusted so that the public offering price per unit
equals $1,000. The number of units, fractional interest of each unit in the
trust, estimated interest distributions per unit and estimated current and long-
term returns will increase or decrease to the extent of any adjustment.

CHANGING YOUR PORTFOLIO. Your trust is not a managed fund. Unlike a managed
fund, we designed your portfolio to remain relatively fixed. Your trust will
generally buy and sell securities:

* to pay expenses,

* to issue additional units or redeem units,

* in limited circumstances to protect the trust,

* as permitted by the trust agreement.

When your trust sells securities, the composition and diversity of the
securities in the portfolio may be altered. However, if the trustee sells

Understanding Your Investment 27

securities to redeem units or pay trust expenses on sales charges, the trustee
will do so, as nearly as practicable, on a pro rata basis. Your trust will
generally reject any offer for securities or other property in exchange for the
securities in its portfolio. If your trust receives securities or other
property, it will either hold the securities or property in the portfolio or
sell the securities or property and distribute the proceeds.

We may increase the size of your trust as we sell units. If we create
additional units, we will seek to replicate the existing portfolio. If your
trust buys securities, it may pay brokerage or other acquisition fees. You
could experience a dilution of your investment because of these fees and
fluctuations in security prices between the time we create units and the time
your trust buys the securities. Because the trusts pay the brokerage fees
associated with the creation of new units and with the sale of securities to
meet redemption and exchange requests, frequent redemption and exchange activity
will likely result in higher brokerage expenses. When your trust buys or sells
securities, we may direct that it place orders with and pay brokerage
commissions to brokers that sell units or are affiliated with your trust or the
trustee.

Pursuant to an exemptive order, your trust may be able to purchase securities
from other trusts that we sponsor when we create additional units. Your trust
may also be able to sell securities to other trusts that we sponsor to satisfy
unit redemption, pay expenses, in connection with periodic tax compliance or in
connection with the termination of your trust. The exemption may enable each
trust to eliminate commission costs on these transactions. The price for those
securities will be the closing price on the sale date on the exchange where the
securities are principally traded as certified by us to the trustee.

AMENDING THE TRUST AGREEMENT. The sponsor and the trustee can change the
trust agreement without your consent to correct any provision that may be
defective or to make other provisions that will not materially adversely affect
your interest (as determined by the sponsor and the trustee). We cannot change
this agreement to reduce your interest in your trust without your consent.
Investors owning two-thirds of the units in your trust may vote to change this
agreement.

TERMINATION OF YOUR TRUST. Your trust will terminate on the mandatory
termination date set forth under "Essential Information" in the "Investment
Summary" section of this prospectus or upon the earlier maturity, payment,
redemption, sale or other liquidation of all of the securities in the portfolio.
The trustee may terminate your trust early if the value of the trust is less
than 40% of the original value of the securities in the trust at the time of
deposit. At this size, the expenses of your trust may create an undue burden on
your investment. Investors owning two-thirds of the units in your trust may
also vote to terminate the trust early. The trustee will liquidate the trust in
the event that a sufficient number of units not yet sold to the public are
tendered for redemption so that the net worth of a trust would be reduced to
less than 40% of the value of the securities at the time they were deposited in
a trust. If this happens, we will refund any sales charge that you paid.

The trustee may also terminate your trust early at the discretion of the
sponsor if the Options are terminated early. The Option Counterparty may
terminate the Options early at its discretion if the trust terminates early.

The trust has the right to terminate all or a portion of the Options prior to
the expiration date by tendering such Options to the Option

28 Understanding Your Investment

Counterparty. This might happen to satisfy unit redemptions, pay trust expenses
or in certain other limited circumstances to protect the trust as described in
this prospectus. Upon certain circumstances laid in at the option agreement,
the Options may upon determination by the Option Counterparty be terminated
early. This may include, but is not limited to the trust terminating early or
the Option Counterparty being unable to hedge the risks associated with the
Options or having the cost of such hedging increase materially. This
determination as to whether to terminate the Options early will be made by the
Option Counterparty at its sole discretion.

The trustee will notify you of any termination and sell any remaining
securities. The trustee will send your final distribution to you within a
reasonable time following liquidation of all the securities after deducting
final expenses. Your termination distribution may be less than the price you
originally paid for your units.

THE SPONSOR. The sponsor of the trust is Advisors Asset Management, Inc. We
are a broker-dealer specializing in providing trading and support services to
broker-dealers, registered representatives, investment advisers and other
financial professionals. Our headquarters are located at 18925 Base Camp Road,
Monument, Colorado 80132. You can contact our unit investment trust division at
8100 East 22nd Street North, Building 800, Suite 102, Wichita, Kansas 67226 or
by using the contacts listed on the back cover of this prospectus. AAM is a
registered broker-dealer and investment adviser, a member of the Financial
Industry Regulatory Authority, Inc. (FINRA) and Securities Investor Protection
Corporation (SIPC) and a registrant of the Municipal Securities Rulemaking Board
(MSRB). If we fail to or cannot perform our duties as sponsor or become
bankrupt, the trustee may replace us, continue to operate your trust without a
sponsor, or terminate your trust.

We and your trust have adopted a code of ethics requiring our employees who
have access to information on trust transactions to report personal securities
transactions. The purpose of the code is to avoid potential conflicts of
interest and to prevent fraud, deception or misconduct with respect to your
trust.

The sponsor or an affiliate may use the list of securities in the trust in
its independent capacity (which may include acting as an investment adviser or
broker-dealer) and distribute this information to various individuals and
entities. The sponsor or an affiliate may recommend or effect transactions in
the securities. This may also have an impact on the price your trust pays for
the securities and the price received upon unit redemption or trust termination.
The sponsor may act as agent or principal in connection with the purchase and
sale of securities, including those held by the trust, and may act as a
specialist market maker in the securities. The sponsor may also issue reports
and make recommendations on the securities in the trust. The sponsor or an
affiliate may have participated in a public offering of one or more of the
securities in the trust. The sponsor, an affiliate or their employees may have
a long or short position in these securities or related securities. An officer,
director or employee of the sponsor or an affiliate may be an officer or
director for the issuers of the securities.

THE TRUSTEE. The Bank of New York Mellon is the trustee of your trust with
its principal unit investment trust division offices located at 2 Hanson Place,
12th Floor, Brooklyn, New York 11217. You can contact the trustee by calling
the telephone number on the back cover of this prospectus or by writing to its
unit

Understanding Your Investment 29

investment trust office. We may remove and replace the trustee in some cases
without your consent. The trustee may also resign by notifying us and
investors.

STANDARD & POOR'S. The S&P 500 Index is a product of S&P Dow Jones Indices
LLC ("SPDJI"), and has been licensed by Advisors Asset Management, Inc. for use
by the trust. Standard & Poor's(R), S&P(R) and S&P 500(R) are registered
trademarks of Standard & Poor's Financial Services LLC ("S&P"); Dow Jones(R) is
a registered trademark of Dow Jones Trademark Holdings LLC ("Dow Jones"); and
these trademarks have been licensed for use by SPDJI and sublicensed for certain
purposes by the trust. The trust is not sponsored, endorsed, sold or promoted
by SPDJI, Dow Jones, S&P, any of their respective affiliates (collectively, "S&P
Dow Jones Indices"). S&P Dow Jones Indices makes no representation or warranty,
express or implied, to the owners of the trust or any member of the public
regarding the advisability of investing in securities generally or in the trust
particularly or the ability of the S&P 500 Index to track general market
performance. S&P Dow Jones Indices' only relationship to the trust with respect
to the S&P 500 Index is the licensing of the Index and certain trademarks,
service marks and/or trade names of S&P Dow Jones Indices or its licensors. The
S&P 500 Index is determined, composed and calculated by S&P Dow Jones Indices
without regard to the trust or its unitholders. S&P Dow Jones Indices have no
obligation to take the needs of the trust or the owners of units into
consideration in determining, composing or calculating the S&P 500 Index. S&P
Dow Jones Indices is not responsible for and has not participated in the
determination of the prices, and amount trust units or the timing of the
issuance or sale of trust units or in the determination or calculation of the
equation by which the trust to be converted into cash, surrendered or redeemed,
as the case may be. S&P Dow Jones Indices has no obligation or liability in
connection with the administration, marketing or trading of units of the trust.
There is no assurance that investment products based on the S&P 500 Index will
accurately track index performance or provide positive investment returns. S&P
Dow Jones Indices LLC is not an investment advisor. Inclusion of a security
within an index is not a recommendation by S&P Dow Jones Indices to buy, sell,
or hold such security, nor is it considered to be investment advice.
Notwithstanding the foregoing, CME Group Inc. and its affiliates may
independently issue and/or sponsor financial products unrelated to the trust
currently but which may be similar to and competitive with the trust. In
addition, CME Group Inc. and its affiliates may trade financial products which
are linked to the performance of the S&P 500 Index.

The Index is unmanaged, not subject to fees, and not available for direct
investment.

HOW WE DISTRIBUTE UNITS. We sell units to the public through broker-dealers
and other firms. We pay part of the sales fee to these distribution firms when
they sell units. Units will be distributed to the public by these firms at the
public offering price per unit as described under "How to Buy Units".

During the initial offering period, the distribution fee (the broker-dealer
concession or agency commission) for broker-dealers and other firms is 3.50% of
the pubic offering price per unit at the time of the transaction.

After the initial offering period, the broker-dealer concession or agency
commission for secondary market transactions is equal to 3.50% of the public
offering price.

30 Understanding Your Investment

Any sales fee discount is borne by the broker-dealer or selling firm out of
the distribution fee. We reserve the right to change the amount of concessions
or agency commissions from time to time.

We currently provide, at our own expense and out of our own profits,
additional compensation and benefits to broker-dealers who sell units of this
trust and our other products. This compensation is intended to result in
additional sales of our products and/or compensate broker-dealers and financial
advisors for past sales. A number of factors are considered in determining
whether to pay these additional amounts. Such factors may include, but are not
limited to, the level or type of services provided by the intermediary, the
level or expected level of sales of our products by the intermediary or its
agents, the placing of our products on a preferred or recommended product list
and access to an intermediary's personnel. We may make these payments for
marketing, promotional or related expenses, including, but not limited to,
expenses of entertaining retail customers and financial advisors, advertising,
sponsorship of events or seminars, obtaining information about the breakdown of
unit sales among an intermediary's representatives or offices, obtaining shelf
space in broker-dealer firms and similar activities designed to promote the sale
of our products. We make such payments to a substantial majority of
intermediaries that sell our products. We may also make certain payments to, or
on behalf of, intermediaries to defray a portion of their costs incurred for the
purpose of facilitating unit sales, such as the costs of developing or
purchasing trading systems to process unit trades. Payments of such additional
compensation described in this paragraph, some of which may be characterized as
"revenue sharing," may create an incentive for financial intermediaries and
their agents to sell or recommend our products, including this trust, over other
products. These arrangements will not change the price you pay for your units.

We generally register units for sale in various states in the U.S. We do not
register units for sale in any foreign country. This prospectus does not
constitute an offer of units in any state or country where units cannot be
offered or sold lawfully. We may reject any order for units in whole or in
part.

We may gain or lose money when we hold units in the primary or secondary
market due to fluctuations in unit prices. The gain or loss is equal to the
difference between the price we pay for units and the price at which we sell or
redeem them. We may also gain or lose money when we deposit securities to
create units. The amount of our profit or loss on the initial deposit of
securities into the trust is shown in the "Notes to Portfolio."

TAXES

This section summarizes some of the main U.S. federal income tax consequences
of owning units of the trust. This section is current as of the date of this
prospectus. Tax laws and interpretations change frequently, and these summaries
do not describe all of the tax consequences to all taxpayers. For example,
these summaries generally do not describe your situation if you are a
corporation, a non U.S. person, a broker/dealer, or other investor with special
circumstances. In addition, this section does not describe your state, local or
foreign tax consequences.

This federal income tax summary is based in part on the advice and opinion of
counsel to the sponsor. The Internal Revenue Service could disagree with any
conclusions set forth in this section. In addition, our counsel was not asked
to

Understanding Your Investment 31

review, and has not reached a conclusion with respect to the federal income tax
treatment of the assets to be deposited in the trust. This may not be
sufficient for you to use for the purpose of avoiding penalties under federal
tax law.

As with any investment, you should seek advice based on your individual
circumstances from your own tax advisor.

TRUST STATUS. The trust intends to be treated as a grantor trust under the
federal tax laws. In grantor trusts, investors are deemed for federal tax
purposes, to own the underlying assets of the trust directly. All taxability
issued are taken into account at the unit holder level. Income passes through
to unit holders as realized by the trust.

Income is reported gross of expenses. Expenses are separately reported based
on a percentage of distributions. Generally, the cash received by unit holders
is the net of income and expenses reported.

The trust is a widely held fixed investment trust ("WHFIT"), and falls under
what is commonly referred to as the WHFIT regulations.

If the trust is at all times operated in accordance with the documents
establishing the trust and certain requirements of federal income tax law are
met, the trust will not be taxed as a corporation for federal income tax
purposes. As a unit owner, you will be treated as the owner of a pro rata
portion of each of the trust assets, and as such you will be considered to have
received a pro rata share of income (e.g., dividends and capital gains, if any)
from each trust asset when such income would be considered to be received by you
if you directly owned the trust assets. As a result, you may be required to
recognize for federal income tax purposes income with respect to the trust
assets in one year even if you do not receive the corresponding distribution
from the trust, or do not receive the corresponding distribution from the trust
until a later year. This is also true even if you elect to have your
distributions reinvested into additional units. In addition, the income from
trust assets that you must take into account for federal income tax purposes is
not reduced by amounts used to pay sales charges or trust expenses.

Under the "Health Care and Education Reconciliation Act of 2010," income from
the trust may also be subject to a new 3.8% "Medicare tax" imposed for taxable
years beginning after 2012. This tax will generally apply to your net
investment income if your adjusted gross income exceeds certain threshold
amounts, which are $250,000 in the case of married couples filing joint returns
and $200,000 in the case of single individuals.

ASSETS OF THE TRUSTS. The trust is expected to hold one or more of the
following: U.S. Treasury Obligations and a contract right that will provide a
return related to the Index.

It is possible that a trust will also hold other assets, including assets
that are treated differently for federal income tax purposes from those
described above, in which case you will have federal income tax consequences
different from or in addition to those described in this section.

U.S. TREASURY OBLIGATIONS. U.S. Treasury obligations are direct obligations
of the United States. Interest paid or accrued on the U.S. Treasury obligations
will be taxable to you at ordinary income tax rates. The highest U.S. federal
income tax rate on ordinary income is currently 39.6%. Certain Treasury
Obligations may have been purchased on the trust's inception date or have bases
attributable

32 Understanding Your Investment

to them of prices of less than their par value at maturity, indicating a market
discount. You may generally elect to recognize this discount over the term of
the obligations or recognize it as ordinary income when the obligations mature.
Certain Treasury Obligations may have been purchased on the trust's inception
date or have bases attributable to them of prices greater than their par value
at maturity, indicating a market premium. You may generally recognize this
premium as a deduction over the term of the obligation. It is intended that the
trust qualify for certain exceptions under the WHFIT rules so that the trustee
will not be reporting bond premium or market discount to you. You should
consult with your tax advisor about calculating the bond premium or market
discount, if any.

OPTION CONTRACT. It is anticipated that the Option will generate capital
gain or loss, which will be long term or short term gain or loss, depending upon
your holding period in the contract at the time the gain or loss is recognized.

YOUR TAX BASIS AND INCOME OR LOSS UPON DISPOSITION. If your trust disposes
of trust assets, you will generally recognize gain or loss. If you dispose of
your units or redeem your units for cash, you will also generally recognize gain
or loss. To determine the amount of this gain or loss, you must subtract your
tax basis in the related trust assets from your share of the total amount
received in the transaction. You can generally determine your initial tax basis
in each trust asset by apportioning the cost of your units, including sales
charges, among the trust assets ratably according to their values on the date
you acquire your units or on the date the assets are acquired by the trust, if
later. In certain circumstances, however, you may have to use information, or
factors, provided by the trustee to adjust your tax basis after you acquire your
units. Trusts that are grantor trusts provide basis information in the form of
factors provided under the WHFIT regulations. Cost basis reporting will treat
each security included in the portfolio of a Trust as a separate item.

If you are an individual, the maximum marginal federal tax rate for net
capital gain is generally 20% (generally 0% for certain taxpayers in the 10% and
15% tax brackets). An additional 3.8% "Medicare tax" may also apply to gain
from the sale or redemption of Units in the Trust, subject to the income
thresholds as described above.

Net capital gain equals net long-term capital gain minus net short-term
capital loss for the taxable year. Capital gain or loss is long term if the
holding period for the asset is more than one year and is short-term if the
holding period for the asset is one year or less. You must exclude the date you
purchase your units to determine your holding period. The tax rates for capital
gains realized from assets held for one year or less are generally the same as
for ordinary income. The Internal Revenue Code, however, treats certain capital
gains as ordinary income in special situations.

If you reinvest the proceeds of a disposition of your units or a disposition
of assets by the trust, all or a portion of any loss you may recognize on the
disposition may be disallowed if your reinvestment is in stocks held directly or
indirectly through the trust.

ROLLOVERS. If you elect to be a rollover unit holder and have your proceeds
from your trust rolled over into a future series of such trust, it is considered
a sale for federal income tax purposes and any gain on the sale will be treated
as a capital gain, and any loss will be treated as a capital loss. However, any
loss you incur in connection with the exchange of your units of the trusts for

Understanding Your Investment 33

units of the next series will generally be disallowed with respect to this
deemed sale and subsequent deemed repurchase, to the extent the two trusts have
substantially identical trust assets under the wash sale provisions of the
Internal Revenue Code.

LIMITATIONS ON THE DEDUCTIBILITY OF TRUST EXPENSES. Generally, for federal
income tax purposes, you must take into account your full pro rata share of your
trust's income, even if some of that income is used to pay trust expenses. You
may deduct your pro rata share of each expense paid by your trust to the same
extent as if you directly paid the expense. You may be required to treat some
or all of the expenses of your trust as miscellaneous itemized deductions.
Individuals may only deduct certain miscellaneous itemized deductions to the
extent they exceed 2% of adjusted gross income.

FOREIGN INVESTORS. Distributions by your trust that are treated as U.S.
source income (e.g., interest on U.S. Treasuries) will generally be subject to
U.S. income taxation and withholding in the case of units held by nonresident
alien individuals, foreign corporations or other non U.S. persons, subject to
any applicable treaty. If you are a foreign investor (i.e., an investor other
than a U.S. citizen or resident or a U.S. corporation, partnership, estate or
trust), you may not be subject to U.S. federal income taxes, including
withholding taxes, on some or all of the income from your trust or on any gain
from the sale or redemption of your units, provided that certain conditions are
met. You may be eligible for an exception from U.S. withholding tax on interest
if you are not a bank and you provide certain information to your financial
professional related to your tax status. With respect to gain, if you are an
individual, gain will not ordinarily be subject to U.S. tax, except as described
below, unless you are present in the U.S. for 183 days or more during a taxable
year. You should consult your tax advisor with respect to the conditions you
must meet in order to be exempt for U.S. tax purposes.

Distributions and dispositions of units after June 30, 2014 may be subject to
a U.S. withholding tax of 30% in the case of distributions to or dispositions by
(i) certain non-U.S. financial institutions that have not entered into an
agreement with the U.S. Treasury to collect and disclose certain information and
are not resident in a jurisdiction that has entered into such an agreement with
the U.S. Treasury and (ii) certain other non-U.S. entities that do not provide
certain certifications and information about the entity's U.S. owners.
Disposition of units by such persons may be subject to such withholding after
December 31, 2016. You should also consult your tax advisor with respect to
other U.S. tax withholding and reporting requirements.

NEW YORK TAX STATUS. Under the existing income tax laws of the State and
City of New York, your trust will not be taxed as a corporation subject to the
New York state franchise tax or the New York City general corporation tax. You
should consult your tax advisor regarding potential foreign, state or local
taxation with respect to your units.

EXPENSES

Your trust will pay various expenses to conduct its operations. The "Fees
and Expenses" section of the "Investment Summary" in this prospectus shows the
estimated amount of these expenses.

Your trust will pay a fee to the trustee for its services. The trustee also
benefits when it holds cash for your trust in non-interest bearing

34 Understanding Your Investment

accounts. Your trust will reimburse us as supervisor, evaluator and sponsor for
providing portfolio supervisory services, for evaluating your portfolio and for
providing bookkeeping and administrative services. Our reimbursements may
exceed the costs of the services we provide to your trust but will not exceed
the costs of services provided to all of our unit investment trusts in any
calendar year. All of these fees may adjust for inflation without your
approval.

Your trust will also pay its general operating expenses. Your trust may pay
expenses such as trustee expenses (including legal and auditing expenses),
various governmental charges, fees for extraordinary trustee services, costs of
taking action to protect your trust, costs of indemnifying the trustee and the
sponsor, legal fees and expenses, expenses incurred in contacting you and costs
incurred to reimburse the trustee for advancing funds to meet distributions.
Your trust will pay a license fee for the use of certain service marks,
trademarks and/or trade names of S&P. Your trust may pay the costs of updating
its registration statement each year. The trustee will generally pay trust
expenses from interest income and principal payments received on the securities
but in some cases may sell securities to pay trust expenses.

EXPERTS

LEGAL MATTERS. Chapman and Cutler LLP acts as counsel for the trust and has
given an opinion that the units are validly issued. Dorsey & Whitney LLP acts
as counsel for the trustee.

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM. Grant Thornton LLP,
independent registered public accounting firm, audited the statement of
financial condition and the portfolio in this prospectus.

ADDITIONAL INFORMATION

This prospectus does not contain all the information in the registration
statement that your trust filed with the Securities and Exchange Commission.
The Information Supplement, which was filed with the Securities and Exchange
Commission, includes more detailed information about the securities in your
portfolio, investment risks and general information about your trust. You can
obtain the Information Supplement by contacting us or the Securities and
Exchange Commission as indicated on the back cover of this prospectus. This
prospectus incorporates the Information Supplement by reference (it is legally
considered part of this prospectus).

Understanding Your Investment 35

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

UNITHOLDERS
ADVISORS DISCIPLINED TRUST 1237

We have audited the accompanying statement of financial condition, including the
trust portfolio on pages 10 and 11, of Advisors Disciplined Trust 1237, as of
____________, 2014, the initial date of deposit. The statement of financial
condition is the responsibility of the trust's sponsor. Our responsibility is
to express an opinion on this statement of financial condition based on our
audit.

We conducted our audit in accordance with auditing standards of the Public
Company Accounting Oversight Board (United States). Those standards require
that we plan and perform the audit to obtain reasonable assurance about whether
the statement of financial condition is free of material misstatement. The
trust is not required to have, nor were we engaged to perform an audit of its
internal control over financial reporting. Our audit included consideration of
internal control over financial reporting as a basis for designing audit
procedures that are appropriate in the circumstances, but not for the purpose of
expressing an opinion on the effectiveness of the trust's internal control over
financial reporting. Accordingly, we express no such opinion. An audit also
includes examining, on a test basis, evidence supporting the amounts and
disclosures in the statement of financial condition, assessing the accounting
principles used and significant estimates made by the sponsor, as well as
evaluating the overall statement of financial condition presentation. Our
procedures included confirmation with The Bank of New York Mellon, trustee, of
cash or an irrevocable letter of credit deposited for the purchase of securities
as shown in the statement of financial condition as of ____________, 2014. We
believe that our audit of the statement of financial condition provides a
reasonable basis for our opinion.

In our opinion, the statement of financial condition referred to above presents
fairly, in all material respects, the financial position of Advisors Disciplined
Trust 1237 as of ____________, 2014, in conformity with accounting principles
generally accepted in the United States of America.

Chicago, Illinois GRANT THORNTON LLP
____________, 2014

ADVISORS DISCIPLINED TRUST 1237

STATEMENT OF FINANCIAL CONDITION AS OF ____________, 2014
-----------------------------------------------------------------------------------------------------------

INVESTMENT IN SECURITIES
Contracts to purchase Treasury Obligations (1)(2) . . . . . . . . . . . . . . . . . . . . . . $
Accrued interest to first settlement date (1) . . . . . . . . . . . . . . . . . . . . . . . .
Cash (3)(4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
----------
Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $
==========

LIABILITIES AND INTEREST OF INVESTORS
Liabilities:
Value of the Options (1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $
Accrued interest payable to sponsor (1) . . . . . . . . . . . . . . . . . . . . . . . . . .
Organization costs (3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
----------

----------

Interest of investors:
Cost to investors (5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Less: sales fee (4)(5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Less: organization costs (3)(5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
----------
Net interest of investors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
----------
Total . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $
==========

Number of units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
==========

Net asset value per unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $
==========

<FN>
(1) The trust invests in a portfolio of Options and Treasury Obligations.
Aggregate cost of the securities is listed under the "Portfolio" and is
based on their underlying value. The trustee will advance the amount of
net interest accrued to the first settlement date to the trust for
distribution to the sponsor as unitholder of record as of such date.
(2) Cash or an irrevocable letter of credit has been deposited with the trustee
covering the funds (aggregating $__________) necessary for the purchase of
securities in the trust represented by purchase contracts.
(3) A portion of the public offering price represents an amount of cash
sufficient to pay for all or a portion of the costs incurred in
establishing the trust. These costs have been estimated at [$3.80] per
unit for the trust. A distribution will be made as of the earlier of the
close of the initial offering period or six months following the trust's
inception date to an account maintained by the trustee from which this
obligation of the investors will be satisfied. To the extent the actual
organization costs are greater than the estimated amount, only the
estimated organization costs added to the public offering price will be
reimbursed to the sponsor and deducted from the assets of the trust.
(4) On the inception date, the total sales fee is [4.50%] of the public
offering price per unit.
(5) The aggregate cost to investors includes the applicable sales fee assuming
no reduction of sales fees.
</FN>

36 Understanding Your Investment

CONTENTS

INVESTMENT SUMMARY
-----------------------------------------------------------------------

A concise description 2 Market Linked Trust
of essential information 2 Investment Objective
about the portfolio 2 Principal Investment Strategy
5 Principal Risks
9 Who Should Invest
9 Essential Information
9 Fees and Expenses
10 Portfolio

UNDERSTANDING YOUR INVESTMENT
-----------------------------------------------------------------------

Detailed information to 12 Option Expiration Examples
help you understand 18 How to Buy Units
your investment 20 How to Sell Your Units
21 Distributions
22 Investment Risks
27 How Your Trust Works
31 Taxes
34 Expenses
35 Experts
35 Additional Information
36 Report of Independent Registered
Public Accounting Firm
36 Statement of Financial Condition

WHERE TO LEARN MORE
-----------------------------------------------------------------------

You can contact us for VISIT US ON THE INTERNET
free information about http://www.aam.us.com
this and other investments, BY E-MAIL
including the Information info@aam.us.com
Supplement CALL ADVISORS ASSET
MANAGEMENT, INC.
(877) 858-1773
CALL THE BANK OF NEW YORK MELLON
(800) 848-6468

ADDITIONAL INFORMATION
-----------------------------------------------------------------------

This prospectus does not contain all information filed with the
Securities and Exchange Commission. To obtain or copy this
information including the Information Supplement (a duplication
fee may be required):

E-MAIL: publicinfo@sec.gov
WRITE: Public Reference Section
Washington, D.C. 20549
VISIT: http://www.sec.gov
(EDGAR Database)
CALL: 1-202-551-8090
(only for information on the operation of the
Public Reference Section)

REFER TO:
ADVISORS DISCIPLINED TRUST 1237

Securities Act file number: 333-195351

Investment Company Act file number: 811-21056

ARMR MLT(SM)
SERIES 2014-1,
S&P 500(R)
PORTFOLIO

PROSPECTUS

____________, 2014

[LOGO]

AAM

ADVISORS
ASSET MANAGEMENT

ADVISORS DISCIPLINED TRUST 1237

ARMR MLT(SM) SERIES 2014-1, S&P 500(R) PORTFOLIO

INFORMATION SUPPLEMENT

This Information Supplement provides additional information concerning each
trust described in the prospectus for the Advisors Disciplined Trust series
identified above. This Information Supplement should be read in conjunction
with the prospectus. It is not a prospectus. It does not include all of the
information that an investor should consider before investing in a trust. It
may not be used to offer or sell units of a trust without the prospectus. This
Information Supplement is incorporated into the prospectus by reference and has
been filed as part of the registration statement with the Securities and
Exchange Commission. Investors should obtain and read the prospectus prior to
purchasing units of a trust. You can obtain the prospectus without charge by
contacting your financial professional or by contacting the unit investment
trust division of Advisors Asset Management, Inc. at 18925 Base Camp Road, Suite
203, Monument, Colorado 80132, at 8100 East 22nd Street North, Building 800,
Suite 102, Wichita, Kansas 67226 or by calling (877) 858-1773. This Information
Supplement is dated as of the date of the prospectus.

CONTENTS

General Information 2
Investment Objective and Policies 3
Risk Factors 5
Administration of the Trust 10
Portfolio Transactions and Brokerage Allocation 19
Purchase, Redemption and Pricing of Units 19
Performance Information 25

GENERAL INFORMATION

Each trust is one of a series of separate unit investment trusts created
under the name Advisors Disciplined Trust and registered under the Investment
Company Act of 1940. Each trust was created as a common law trust on the
inception date described in the prospectus under the laws of the state of
New York. Each trust was created under a trust agreement among Advisors Asset
Management, Inc. (as sponsor, evaluator and supervisor) and The Bank of New York
Mellon (as trustee).

When your trust was created, the sponsor delivered to the trustee
securities or contracts for the purchase thereof for deposit in the trust and
the trustee delivered to the sponsor documentation evidencing the ownership of
units of the trust. At the close of the New York Stock Exchange on the trust's
inception date, the number of units may be adjusted so that the public offering
price per unit equals $1,000. The number of units, fractional interest of each
unit in the trust will increase or decrease to the extent of any adjustment.
Additional units of each trust may be issued from time to time by depositing in
the trust additional securities (or contracts for the purchase thereof together
with cash or irrevocable letters of credit) or cash (including a letter of
credit or the equivalent) with instructions to purchase additional securities.
As additional units are issued by a trust as a result of the deposit of
additional securities by the sponsor, the aggregate value of the securities in
the trust will be increased and the fractional undivided interest in the trust
represented by each unit will be decreased. The sponsor may continue to make
additional deposits of securities into a trust, provided that such additional
deposits will be in amounts, which will generally maintain the existing
relationship among the principal amounts and number of contracts in such trust.
Thus, although additional units will be issued, each unit will generally
continue to represent the same principal amount and number of contracts of each
security. If the sponsor deposits cash to purchase additional securities,
existing and new investors may experience a dilution of their investments and a
reduction in their anticipated income because of fluctuations in the prices of
the securities between the time of the deposit and the purchase of the
securities and because the trust will pay any associated brokerage fees.

The trustee has not participated in the selection of the securities
deposited in the trust and has no responsibility for the composition of the
trust portfolio.

Each unit initially offered represents an undivided interest in the related
trust. To the extent that any units are redeemed by the trustee or additional
units are issued as a result of additional securities being deposited by the
sponsor, the fractional undivided interest in a trust represented by each
unredeemed unit will increase or decrease accordingly, although the actual
interest in such trust represented by such fraction will remain unchanged.
Units will remain outstanding until redeemed upon tender to the trustee by
unitholders, which may include the sponsor, or until the termination of the
trust agreement.

A trust consists of (a) the securities listed under "Portfolio" in the
prospectus as may continue to be held from time to time in the trust, (b) any
additional securities acquired and held by the trust pursuant to the provisions
of the trust agreement and (c) any cash held in the accounts of the trust. All
or a portion of the Treasury Obligations are pledged as collateral in order to

-2-

secure repayment of the trust's obligation to pay an option premium to the
Option Counterparty at the expiration of the options. Neither the sponsor nor
the trustee shall be liable in any way for any failure in any of the securities.
However, should any contract for the purchase of any of the securities initially
deposited in a trust fail, the sponsor will, unless substantially all of the
moneys held in the trust to cover such purchase are reinvested in substitute
securities in accordance with the trust agreement, refund the cash and sales fee
attributable to such failed contract to all unitholders on the next distribution
date.

INVESTMENT OBJECTIVE AND POLICIES

The trust seeks to provide capital appreciation linked to the Index and
repayment at scheduled trust termination of [$1,010] per unit, subject to the
credit of the Reference Issuer along with potential for income. The prospectus
provides additional information regarding the trust's objective and investment
strategy.

The trust is a unit investment trust and is not an "actively managed" fund.
Traditional methods of investment management for a managed fund typically
involve frequent changes in a portfolio of securities on the basis of economic,
financial and market analysis. The portfolio of a trust, however, will not be
actively managed and therefore the adverse financial condition of an issuer will
not necessarily require the sale of its securities from a portfolio.

The sponsor may not alter the portfolio of a trust by the purchase, sale or
substitution of securities, except in special circumstances as provided in the
trust agreement. Thus, the assets of a trust will generally remain unchanged
under normal circumstances. The trust agreement provides that the sponsor may
(but need not) direct the trustee to dispose of a security in certain events
such as the issuer having defaulted on the payment on any of its outstanding
obligations or the price of a security has declined to such an extent or other
such credit factors exist so that in the opinion of the supervisor the retention
of such securities would be detrimental to the trust.

The trustee may sell securities, designated by the supervisor, from a trust
for the purpose of redeeming units of such trust tendered for redemption and the
payment of expenses.

The trust has the right to terminate all or a portion of the Options prior
to the expiration date by tendering such Options to the Option Counterparty.
This might happen to satisfy unit redemptions, pay trust expenses or in certain
other limited circumstances to protect the trust as described in this
prospectus. Under certain circumstances laid out in the Option agreement, the
Options may automatically or upon determination by the Option Counterparty be
terminated early. This may include, but is not limited to changes in law, the
Option Counterparty being unable to hedge the risk associated with the Options
or having the cost of such hedging increase materially. The determinations as
to whether to terminate the Options early will be made by the Option
Counterparty at its sole discretion. The trustee may also terminate your trust
early at the discretion of the sponsor if the Options are terminated early by
the Option Counterparty.

Because certain of the securities in certain of the trusts may from time to
time under certain circumstances be sold, exercised, redeemed, will mature in
accordance with their terms, terminate or otherwise liquidated and because the
proceeds from such events will be distributed

-3-

to unitholders and will not be reinvested, no assurance can be given that a
trust will retain for any length of time its present size and composition.
Neither the sponsor nor the trustee shall be liable in any way for any default,
failure or defect in any security. In the event of a failure to deliver any
security that has been purchased for a trust under a contract ("Failed
Securities"), the sponsor is authorized under the trust agreement to direct the
trustee to acquire other securities ("Replacement Securities") to make up the
original corpus of such trust.

The Replacement Securities must be purchased within 20 days after delivery
of the notice that a contract to deliver a security will not be honored and the
purchase price may not exceed the amount of funds reserved for the purchase of
the Failed Securities. The Replacement Securities for securities other than the
Treasury Obligations must be securities of the type selected for the trust and
must not adversely affect the federal income tax status of the trust.

The Replacement Securities for failed Treasury Obligations (i) shall be
bonds, debentures, notes or other straight debt obligations (whether secured or
unsecured and whether senior or subordinated) without equity or other conversion
features, with fixed maturity dates substantially the same as those of the
Failed Securities, having no warrants or subscription privileges attached;
(ii) shall be payable in United States currency; (iii) shall not be "when, as
and if issued" obligations or restricted securities; (iv) shall be issued after
July 18, 1984 if interest thereon is United States source income; (v) shall be
issued or guaranteed by an issuer subject to or exempt from the reporting
requirements under Section 13 or 15(d) of the Securities Exchange Act of 1934
(or similar provisions of law) or in effect guaranteed, directly or indirectly,
by means by of a lease agreement, agreement to buy securities, services or
products, or other similar commitment of the credit of such an issuer to the
payment of the Replacement Securities; and (vi) shall not cause the units of the
related trust to cease to be rated "AAA" by Standard & Poor's, a division of The
McGraw-Hill Companies, Inc. if the units are so rated. For the Treasury
Obligations, the purchase price of the Replacement Securities (exclusive of
accrued interest) shall not exceed the principal attributable to the Failed
Securities.

Whenever a Replacement Security is acquired for a trust, the trustee shall
notify all unitholders of the trust of the acquisition of the Replacement
Security and shall, on the next monthly distribution date which is more than 30
days thereafter, make a pro rata distribution of the amount, if any, by which
the cost to the trust of the Failed Security exceeded the cost of the
Replacement Security. Once all of the securities in a trust are acquired, the
trustee will have no power to vary the investments of the trust, i.e., the
trustee will have no managerial power to take advantage of market variations to
improve a unitholder's investment.

If the right of limited substitution described in the preceding paragraphs
is not utilized to acquire Replacement Securities in the event of a failed
contract, the sponsor will refund the sales fee attributable to such Failed
Securities to all unitholders of the trust and the trustee will distribute the
cash attributable to such Failed Securities not more than 30 days after the date
on which the trustee would have been required to purchase a Replacement
Security. In addition, unitholders should be aware that, at the time of receipt
of such cash, they may not be able to reinvest such proceeds in other securities
at a return equal to or in excess of the return which such proceeds would have
earned for unitholders of such trust.

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In the event that a Replacement Security is not acquired by a trust, the
income for such trust may be reduced. Whether or not a Replacement Security for
a Treasury Obligation is acquired, an amount equal to the accrued interest (at
the coupon rate of the failed Treasury Obligation) will be paid to unitholders
of the trust to the date the sponsor removes the failed Treasury Obligation from
the trust if the sponsor determines not to purchase a Replacement Security or to
the date of substitution if a Replacement Security is purchased. All such
interest paid to unitholders which accrued after the date of settlement for a
purchase of units will be paid by the sponsor. In the event a Replacement
Security could not be acquired by a trust, the net annual interest income per
unit for such trust would be reduced.

To the best of the sponsor's knowledge, there is no litigation pending as
of the trust's inception in respect of any security that might reasonably be
expected to have a material adverse effect on the trust. At any time after the
trust's inception, litigation may be instituted on a variety of grounds with
respect to the securities. The sponsor is unable to predict whether any such
litigation may be instituted, or if instituted, whether such litigation might
have a material adverse effect on the trust. The sponsor and the trustee shall
not be liable in any way for any default, failure or defect in any security.

RISK FACTORS

MARKET RISK is the risk that the value of the securities in your trust will
fluctuate. This could cause the value of your units to fall below your original
purchase price or below the principal value. Market value fluctuates in response
to various factors. These can include changes in interest rates, inflation, the
financial condition of a security's issuer, perceptions of the issuer, or
ratings on a security. While the Options are related to the performance of the
Index, the return on the Options at expiration depends on the Index level on
that date and whether a Credit Event has occurred with respect to the Reference
Issuer prior to expiration. The terms of the Options provide for Options
liquidated prior to their expiration to have amounts owed between the trust and
the Option Counterparty to be determined by the Calculation Agent (who is
generally the Option Counterparty) in good faith and using commercially
reasonable procedures. The scheduled Option expiration date is ____________,
2020. Even though we supervise your portfolio, you should remember that we do
not manage your portfolio. Your trust will not sell a security solely because
the market value falls as is possible in a managed fund. The trust does not
guarantee any return of principal.

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political or economic events. If the Option Counterparty defaults on any payment
that becomes due to the trust, to the extent not covered by posted collateral,
if any, the trust may suffer losses, be unable to achieve its investment
objective and it may result in a reduction in the value of your units. If the
Index Final Value is greater than the Index Starting Value (i.e. an increase in
the value of the Index) and the Option Counterparty becomes insolvent, you
should not expect to receive any capital appreciation linked to the performance
of the Index. If the Option Counterparty becomes insolvent and the trust is owed
a net payment on the Options from the Option Counterparty, the trust may not be
able to recover any such amounts owed. If the Option Counterparty becomes
insolvent and the trust owes a net payment on the Options to the Option
Counterparty, the Options may be terminated early and the trust may be required
to make this payment prior to the Options' scheduled expiration date. This could
result in a loss to the trust on the Options prior to the Options' scheduled
expiration date where a loss may not have otherwise been experienced if the
Options were held to their scheduled expiration date.

Index Risk. The policies of the Index sponsor and any changes affecting the
Index or the Index constituents could affect the market value of the trust and
its units. The policies of the Index sponsor concerning the calculation of the
levels of the Index or additions, deletions or substitutions of the Index
constituents and the manner in which changes affecting such Index constituents
or their issuers, such as stock dividends, reorganizations or mergers, are
reflected in the level of the Index, could affect the levels of the Index and,
therefore, the amount payable in respect of units of the trust on the
termination date and the market value of the trust and its units prior to the
termination date. The market value of the trust and its units could also be
affected if the Index sponsor changes these policies, for example, by changing
the manner in which it calculates the level of the Index, or if the Index
sponsor discontinues or suspends calculation or publication of the level of the
Index, in which case it may become difficult to determine the market value of
the trust and its units. Unitholders will have no rights against the Index
sponsor, even if the Index sponsor decides to suspend the calculation of the
Index and this suspension adversely impacts the amount unitholders receive at
termination.

THE OPTIONS. The return on the Options at expiration depends on the
performance of the Index and whether a Credit Event occurs with respect to the
Reference Issuer of the Reference Obligation prior to expiration. The terms of
the Options provide for Options liquidated prior to

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their expiration to have amounts owed between the trust and the Option
Counterparty to be determined by the Calculation Agent (which is generally the
Option Counterparty) in good faith and using commercially reasonable procedures.
The scheduled Option expiration date is [____________, 2020]. In addition,
litigation regarding the Option Counterparty or of the industries represented by
the Option Counterparty may negatively impact the values of the Options.

Disruptions or suspensions of trading in the securities markets or the
Index may make valuation of the Options difficult. If such a disruption occurs
at or near the expiration date of the Options, there may be a delay in
calculation of the Option payment at expiration of the Options and/or a delay in
any payment by the Option Counterparty of as many as eight days. If a
postponement occurs, the calculation agent for the Options would typically
determine the Option payment, price or other amount with respect to that
valuation date on the first succeeding business day on which no disruption event
occurs or is continuing. The Options may limit the amount of time that such a
postponement may continue. If a disruption event occurs on the last possible
date for calculating the Option payment, the calculation agent may make a good
faith estimate of the Option payment that would have prevailed in the absence of
the market disruption. Any market disruption or delay in valuation as a result
of any disruption could have an adverse affect on the trust and the value of
units.

The trust has the right to terminate all or a portion of the Options prior
to the expiration date by tendering such Options to the Option Counterparty.
This might happen to satisfy unit redemptions, pay trust expenses or in certain
other limited circumstances to protect the trust as described in this
prospectus. Upon certain circumstances laid in at the option agreement, the
Options may upon determination by the Option Counterparty be terminated early.
This may include, but is not limited to the trust terminating early or the
Option Counterparty being unable to hedge the risks associated with the Options
or having the cost of such hedging increase materially. This determination as to
whether to terminate the Options early will be made by the Option Counterparty
at its sole discretion.

The Option Counterparty or an affiliate thereof will generally act as
Calculation Agent for the Options. Upon a default by the Option Counterparty,
the trust's sponsor will become the Calculation Agent. The duties of the
Calculation Agent include making determinations that affect the Options, such as
determining the returns used to determine the final payment by the Options,
calculating the value of the Options if Options are tendered for early
termination, determining adjustments with respect to the Options whether to
postpone payment due to a market or or other event. The exercise of these duties
could adversely affect the value of the Options and may present a conflict of
interest between the Calculation Agent and the trust. In addition, the Option
Counterparty or an affiliate determines the value at which the trust may
terminate the Options. The exercise of this duty by the Option Counterparty or
its affiliate could adversely affect the value of the Options and presents a
conflict of interest between the Option Counterparty and the trust. Neither the
sponsor nor the trustee are affiliated with the Option Counterparty.

The Options' formula has a negative adjustment of [2%] with respect to the
Index. As a result, the amount realized on the Options will generally be less
than any appreciation of the Index. The Option payment related to the Index
and, as a result, the trust return is subject to a

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capped upside. If the Index Final Value is more than [42]% over the Index
Starting Value, the amount realized on the Options will be capped at [40%] and
will be less than the performance of the Index.

The trust is designed to provide an amount per unit at scheduled
termination of [$1,010] plus a potential amount linked to the Index performance.
The trust will not return [$1,010] per unit at scheduled trust termination in
certain circumstances. These circumstances may include, but are not necessarily
limited to, if a Credit Event occurs with respect to the Reference Issuer, the
Options are terminated early by the Option Counterparty or the trust, the trust
terminates early, units of the trust are redeemed early, the Option Counterparty
defaults on its obligations, or the trust disposes of Options or Treasury
Obligations for any reason, including to pay unit redemptions or trust expenses,
due to adverse credit factors affecting the Option Counterparty or due to
adverse tax law changes affecting treatment of the Options. If trust operating
expenses exceed the interest income received by the trust on the Treasury
Obligations, the trustee would need to sell Options and/or Treasury Obligations
to pay trust expenses and the trust would not achieve its objectives.

U.S. TREASURY OBLIGATIONS. U.S. Treasury obligations are direct
obligations of the United States which are backed by the full faith and credit
of the United States. There is no guarantee that the U.S. government will be
able to satisfy its interest payment obligations to the trust over the life of
the trust. The value of the Treasury Obligations will be adversely affected by
decreases in bond prices and increases in interest rates. Certain Treasury
Obligations may have been purchased on the trust's inception date at prices of
less than their par value at maturity, indicating a market discount. Other
Treasury Obligations may have been purchased on the Initial Date of Deposit at
prices greater than their par value at maturity, indicating a market premium.
The coupon interest rate of Treasury Obligations purchased at a market discount
was lower than current market interest rates of newly issued bonds of comparable
rating and type and the coupon interest rate of Treasury Obligations purchased
at a market premium was higher than current market interest rates of newly
issued bonds of comparable rating and type. Generally, the value of bonds
purchased at a market discount will increase in value faster than bonds
purchased at a market premium if interest rates decrease. Conversely, if
interest rates increase, the value of bonds purchased at a market discount will
decrease faster than bonds purchased at a market premium. A portion of the
Treasury Obligations held by the trust will be segregated by the trustee as
collateral in order to secure the trust's obligation to pay the Option premium.

MARKET DISCOUNTS AND PREMIUMS. Certain of the Treasury Obligations in
certain of the trusts may have been acquired at a market discount from par value
at maturity. The coupon interest rates on the discount Treasury Obligations at
the time they were purchased and deposited in the trusts were lower than the
current market interest rates for newly issued bonds of comparable rating and
type. If such interest rates for newly issued comparable Treasury Obligations
increase, the market discount of previously issued Treasury Obligations will
become greater, and if such interest rates for newly issued comparable Treasury
Obligations decline, the market discount of previously issued Treasury
Obligations will be reduced, other things being equal. Investors should also
note that the value of Treasury Obligations purchased at a market discount will
increase in value faster than Treasury Obligations purchased at a market premium
if interest rates decrease. Conversely, if interest rates increase, the value
of Treasury Obligations

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purchased at a market discount will decrease faster than Treasury Obligations
purchased at a market premium. In addition, if interest rates rise, the
prepayment risk of higher yielding, premium Treasury Obligations and the
prepayment benefit for lower yielding, discount Treasury Obligation will be
reduced. A discount Treasury Obligation held to maturity will have a larger
portion of its total return in the form of taxable income and capital gain and
loss in the form of tax-exempt interest income than a comparable Treasury
Obligation newly issued at current market rates. Market discount attributable
to interest changes does not indicate a lack of market confidence in the issue.
Neither the sponsor nor the trustee shall be liable in any way for any default,
failure or defect in any of the Treasury Obligations.

Certain of the Treasury Obligations held by the trust may have been
acquired at a market premium from par value at maturity. The coupon interest
rates on the premium Treasury Obligations at the time they were purchased by the
trust were higher than the current market interest rates for newly issued
Treasury Obligations of comparable rating and type. If such interest rates for
newly issued and otherwise comparable Treasury Obligations decrease, the market
premium of previously issued Treasury Obligations will be increased, and if such
interest rates for newly issued comparable Treasury Obligations increase, the
market premium of previously issued Treasury Obligations will be reduced, other
things being equal. The current returns of Treasury Obligations trading at a
market premium are initially higher than the current returns of comparable
Treasury Obligations of a similar type issued at currently prevailing interest
rates because premium Treasury Obligations tend to decrease in market value as
they approach maturity when the face amount becomes payable. Because part of
the purchase price is thus returned not at maturity but through current income
payments, early redemption of a premium Treasury Obligation at par or early
prepayments of principal will result in a reduction in yield. Redemption
pursuant to call provisions generally will, and redemption pursuant to sinking
fund provisions may, occur at times when the redeemed Treasury Obligations have
an offering side valuation which represents a premium over par or for original
issue discount Treasury Obligations a premium over the accreted value.

LIQUIDITY RISK is the risk that the value of a security will fall if
trading activity in the security is limited or absent. No on can guarantee that
a liquid trading market will exist for any security because these securities
generally trade in the over-the-counter market (they are not listed on a
securities exchange). In particular, there may not be any secondary market for
the Options. Upon issuance, the Options will not have an established trading
market and were not registered by the issuer under the Securities Act of 1933.
This could adversely affect the trust and the value of units.

__________ RISK. The trust is exposed to risks associated with the
Reference Issuer which is a company in the __________ industry. Negative
developments in the _________ industry may affect the value of your investment
more than would be the case in a more diversified investment.

-9-

EARLY TRUST TERMINATION. The trustee has the power to terminate your trust
early in limited cases as described under "Understanding Your Investment--How
Your Trust Works--Termination of Your Trust". If the trust terminates early,
the trust may suffer losses and be unable to achieve its investment objective.
This could result in a reduction in the value of units and result in a
significant loss to investors even if no credit event occurs with respect to the
Reference Issuer.

EARLY OPTION TERMINATION BY OPTION COUNTERPARTY. Upon certain
circumstances laid out in the option agreement, the Options may be terminated
early upon determination by the Option Counterparty as described under
"Investment Summary--Principal Investment Strategy--Early Option Termination or
Liquidation". An early termination of the Options may result in the early
termination of the trust and/or the trust being unable to achieve its investment
objective and result in a reduction in the value of your units.

ADDITIONAL DEPOSITS. The trust agreement authorizes the sponsor to
increase the size of a trust and the number of units thereof by the deposit of
additional securities, or cash (including a letter of credit or the equivalent)
with instructions to purchase additional securities, in such trust and the
issuance of a corresponding number of additional units. In connection with
these deposits, existing and new investors may experience a dilution of their
investments and a reduction in their anticipated income because of fluctuations
in the prices of the securities between the time of the deposit and the purchase
of the securities and because a trust will pay the associated brokerage fees and
other acquisition costs.

ADMINISTRATION OF THE TRUST

DISTRIBUTIONS TO UNITHOLDERS. Income received by a trust, including that
part of the proceeds of any disposition of Treasury Obligations which represent
accrued interest, is credited by the trustee to the Income Account for the
trust. All other receipts are credited by the trustee to a separate Capital
Account for the trust. The trustee will normally distribute any income
received by a trust on each distribution date or shortly thereafter to
unitholders of record on the preceding record date. Unitholders will receive an
amount substantially equal to their pro rata share of the available balance of
the Income Account of the trust. All distributions will be net of applicable
expenses. There is no assurance that any actual distributions will be made
since all income received may be used to pay expenses. In addition, excess
amounts from the Capital Account of a trust, if any, will be distributed on each
distribution date or shortly thereafter to the unitholders of record on the
preceding record date. The trustee is not required to make a distribution from
the Income Account or the Capital Account unless the total cash held for
distribution equals at least 0.1% of the trust's net asset value as determined
under the trust agreement. Proceeds received from the disposition of any of the
securities after a record date and prior to the following distribution date will
be held in the Capital Account and not distributed

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until the next distribution date applicable to the Capital Account. The trustee
shall be required to make a distribution from the Capital Account if the cash
balance on deposit therein available for distribution shall be sufficient to
distribute at least $1.00 per unit. The trustee is not required to pay interest
on funds held in the Capital or Income Accounts (but may itself earn interest
thereon and therefore benefits from the use of such funds).

The distribution to the unitholders as of each record date will be made on
the following distribution date or shortly thereafter and shall consist of an
amount substantially equal to the unitholders' pro rata share of the available
balance of the Income Account of the trust after deducting estimated expenses.
Because investment income payments are not received by a trust at a constant
rate throughout the year, such distributions to unitholders are expected to
fluctuate. Persons who purchase units will commence receiving distributions
only after such person becomes a record owner. A person will become the owner
of units, and thereby a unitholder of record, on the date of settlement provided
payment has been received. Notification to the trustee of the transfer of units
is the responsibility of the purchaser, but in the normal course of business the
selling broker-dealer provides such notice.

The trustee will periodically deduct from the Income Account of a trust
and, to the extent funds are not sufficient therein, from the Capital Account of
a trust amounts necessary to pay the expenses of the trust. The trustee also
may withdraw from said accounts such amounts, if any, as it deems necessary to
establish a reserve for any governmental charges payable out of a trust.
Amounts so withdrawn shall not be considered a part of a trust's assets until
such time as the trustee shall return all or any part of such amounts to the
appropriate accounts. In addition, the trustee may withdraw from the Income and
Capital Accounts of a trust such amounts as may be necessary to cover
redemptions of units.

STATEMENTS TO UNITHOLDERS. With each distribution, the trustee will
furnish to each unitholder a statement of the amount of income and the amount of
other receipts, if any, which are being distributed, expressed in each case as a
dollar amount per unit.

The accounts of a trust are required to be audited annually, at the related
trust's expense, by independent public accountants designated by the sponsor,
unless the sponsor determines that such an audit would not be in the best
interest of the unitholders of the trust. The accountants' report will be
furnished by the trustee to any unitholder upon written request. Within a
reasonable period of time after the end of each calendar year, the trustee shall
furnish to each person who at any time during the calendar year was a unitholder
of a trust a statement, covering the calendar year, setting forth for the trust:

(A) As to the Income Account:

(1) the amount of income received on the securities (including income
received as a portion of the proceeds of any disposition of
securities);

(2) the amounts paid for purchases of replacement securities or for
purchases of securities otherwise pursuant to the trust
agreement, if any, and for redemptions;

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(3) the deductions, if any, from the Income Account for payment into
the Reserve Account;

(4) the deductions for applicable taxes and fees and expenses of the
trustee, the depositor, the evaluator, the supervisor, counsel,
auditors and any other expenses paid by the trust;

(5) the amounts reserved for purchases of contract securities, for
purchases made pursuant to replace failed contract securities or
for purchases of securities otherwise pursuant to the trust
agreement, if any;

(6) the deductions for payment of the depositor's expenses of
maintaining the registration of the trust units, if any;

(7) the aggregate distributions to unitholders; and

(8) the balance remaining after such deductions and distributions,
expressed both as a total dollar amount and as a dollar amount
per unit outstanding on the last business day of such calendar
year;

(B) As to the Capital Account:

(1) the net proceeds received due to sale, maturity, redemption,
liquidation or disposition of any of the securities, excluding
any portion thereof credited to the Income Account;

(2) the amount paid for purchases of replacement securities or for
purchases of securities otherwise pursuant to the trust
agreement, if any, and for redemptions;

(3) the deductions, if any, from the Capital Account for payments
into the Reserve Account;

(4) the deductions for payment of applicable taxes and fees and
expenses of the trustee, the depositor, the evaluator, the
supervisor, counsel, auditors and any other expenses paid by the
trust;

(5) the deductions for payment of the depositor's expenses of
organizing the trust;

(6) the amounts reserved for purchases of contract securities, for
purchases made pursuant to replace failed contract securities or
for purchases of securities otherwise pursuant to the trust
agreement, if any;

(7) the deductions for payment of deferred sales fee and creation and
development fee, if any;

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(8) the deductions for payment of the depositor's expenses of
maintaining the registration of the trust units, if any;

(9) the aggregate distributions to unitholders; and

(10) the balance remaining after such distributions and deductions,
expressed both as a total dollar amount and as a dollar amount
per unit outstanding on the last business day of such calendar
year; and

(1) a list of the securities held as of the last business day of such
calendar year and a list which identifies all securities sold or
other securities acquired during such calendar year, if any;

(2) the number of units outstanding on the last business day of such
calendar year;

(3) the unit value based on the last trust evaluation of such trust
made during such calendar year; and

(4) the amounts actually distributed during such calendar year from
the Income and Capital Accounts, separately stated, expressed
both as total dollar amounts and as dollar amounts per unit
outstanding on the record dates for such distributions.

RIGHTS OF UNITHOLDERS. A unitholder may at any time tender units to the
trustee for redemption. The death or incapacity of any unitholder will not
operate to terminate a trust nor entitle legal representatives or heirs to claim
an accounting or to bring any action or proceeding in any court for partition or
winding up of a trust. No unitholder shall have the right to control the
operation and management of a trust in any manner, except to vote with respect
to the amendment of the trust agreement or termination of a trust.

AMENDMENT AND TERMINATION. The trust agreement may be amended from time to
time by the sponsor and trustee or their respective successors, without the
consent of any of the unitholders, (i) to cure any ambiguity or to correct or
supplement any provision which may be defective or inconsistent with any other
provision contained in the trust agreement, (ii) to make such other provision in
regard to matters or questions arising under the trust agreement as shall not
materially adversely affect the interests of the unitholders or (iii) to make
such amendments as may be necessary (a) for the trust to continue to qualify as
a regulated investment company for federal income tax purposes if the trust has
elected to be taxed as such under the United States Internal Revenue Code of
1986, as amended, or (b) to prevent the trust from being deemed an association
taxable as a corporation for federal income tax purposes if the trust has not
elected to be taxed as a regulated investment company under the United States
Internal Revenue Code of 1986, as amended. The trust agreement may not be
amended, however, without the consent of all unitholders then outstanding, so as
(1) to permit, except in accordance with the terms and

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conditions thereof, the acquisition hereunder of any securities other than those
specified in the schedules to the trust agreement or (2) to reduce the
percentage of units the holders of which are required to consent to certain of
such amendments. The trust agreement may not be amended so as to reduce the
interest in a trust represented by units without the consent of all affected
unitholders. Except for the amendments, changes or modifications described
above, neither the sponsor nor the trustee may consent to any other amendment,
change or modification of the trust agreement without the giving of notice and
the obtaining of the approval or consent of unitholders representing at least 66
2/3% of the units then outstanding of the affected trust. No amendment may
reduce the aggregate percentage of units the holders of which are required to
consent to any amendment, change or modification of the trust agreement without
the consent of the unitholders of all of the units then outstanding of the
affected trust and in no event may any amendment be made which would (1) alter
the rights to the unitholders as against each other, (2) provide the trustee
with the power to engage in business or investment activities other than as
specifically provided in the trust agreement, (3) adversely affect the tax
status of the trust for federal income tax purposes or result in the units being
deemed to be sold or exchanged for federal income tax purposes or (4) unless the
trust has elected to be taxed as a regulated investment company for federal
income tax purposes, result in a variation of the investment of unitholders in
the trust. The trustee will notify unitholders of the substance of any such
amendment.

The trust agreement provides that a trust shall terminate upon the
maturity, liquidation, redemption or other disposition of the last of the
securities held in the trust but in no event is it to continue beyond the
mandatory termination date. If the value of a trust shall be less than the
applicable minimum value stated in the prospectus (generally 40% of the total
value of securities deposited in the trust during the initial offering period),
the trustee may, in its discretion, and shall, when so directed by the sponsor,
terminate the trust. The trustee may also terminate your trust early at the
discretion of the sponsor if the Options are terminated early by the Option
Counterparty. The Option Counterparty may terminate the Options early at its
discretion for a variety of reasons including, but not limited to, suspension,
cancellation or material adjustments to the Index, certain changes in law, the
Option Counterparty being unable to hedge the risk associated with the Options
or having the cost of such hedging increase materially. The Index sponsor is an
affiliate of the Option Counterparty and may adjust, suspend or terminate the
Index in its sole and absolute discretion. A trust may be terminated at any
time by the holders of units representing 66 2/3% of the units thereof then
outstanding. In addition, the sponsor may terminate a trust if it is based on a
security index and the index is no longer maintained. A trust will be
liquidated by the trustee in the event that a sufficient number of units of the
trust not yet sold are tendered for redemption by the sponsor, so that the net
worth of the trust would be reduced to less than 40% of the value of the
securities at the time they were deposited in the trust. If a trust is
liquidated because of the redemption of unsold units by the sponsor, the sponsor
will refund to each purchaser of units the entire sales fee paid by such
purchaser.

Beginning nine business days prior to, but no later than, the scheduled
termination date described in the prospectus, the trustee may begin to sell all
of the remaining underlying securities on behalf of unitholders in connection
with the termination of the trust. The sponsor may assist the trustee in these
sales and receive compensation to the extent permitted by applicable law. The
sale proceeds will be net of any incidental expenses involved in the sales.

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The sponsor will generally instruct the trustee to sell the securities as
quickly as practicable during the termination proceedings without in its
judgment materially adversely affecting the market price of the securities, but
it is expected that all of the securities will in any event be disposed of
within a reasonable time after a trust's termination. The sponsor does not
anticipate that the period will be longer than one month, and it could be as
short as one day, depending on the liquidity of the securities being sold. The
liquidity of any security depends on the daily trading volume of the security
and the amount that the sponsor has available for sale on any particular day.
Of course, no assurances can be given that the market value of the securities
will not be adversely affected during the termination proceedings.

Approximately thirty days prior to termination of a trust, the trustee will
notify unitholders of the termination.

Within a reasonable period after termination, the trustee will sell any
securities remaining in a trust and, after paying all expenses and charges
incurred by the trust, will distribute to unitholders thereof their pro rata
share of the balances remaining in the Income and Capital Accounts of the trust.

The sponsor may, but is not obligated to, offer for sale units of a
subsequent series of a trust at approximately the time of the mandatory
termination date. If the sponsor does offer such units for sale, unitholders
may be given the opportunity to purchase such units at a public offering price
that includes a reduced sales fee. There is, however, no assurance that units
of any new series of a trust will be offered for sale at that time, or if
offered, that there will be sufficient units available for sale to meet the
requests of any or all unitholders.

THE TRUSTEE. The trustee is The Bank of New York Mellon, a trust company
organized under the laws of New York. The Bank of New York Mellon has its
principal unit investment trust division offices at 2 Hanson Place, 12th Floor,
Brooklyn, New York 11217, (800) 848-6468. The Bank of New York Mellon is subject
to supervision and examination by the Superintendent of Banks of the State of
New York and the Board of Governors of the Federal Reserve System, and its
deposits are insured by the Federal Deposit Insurance Corporation to the extent
permitted by law.

The trustee, whose duties are ministerial in nature, has not participated
in selecting the portfolio of any trust. In accordance with the trust
agreement, the trustee shall keep records of all transactions at its office.
Such records shall include the name and address of, and the number of units held
by, every unitholder of a trust. Such books and records shall be open to
inspection by any unitholder at all reasonable times during usual business
hours. The trustee shall make such annual or other reports as may from time to
time be required under any applicable state or federal statute, rule or
regulation. The trustee shall keep a certified copy or duplicate original of
the trust agreement on file in its office available for inspection at all
reasonable times during usual business hours by any unitholder, together with a
current list of the securities held in each trust. Pursuant to the trust
agreement, the trustee may employ one or more agents for the purpose of custody
and safeguarding of securities comprising a trust.

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Under the trust agreement, the trustee or any successor trustee may resign
and be discharged of a trust created by the trust agreement by executing an
instrument in writing and filing the same with the sponsor.

The trustee or successor trustee must mail a copy of the notice of
resignation to all unitholders then of record, not less than sixty days before
the date specified in such notice when such resignation is to take effect. The
sponsor upon receiving notice of such resignation is obligated to appoint a
successor trustee promptly. If, upon such resignation, no successor trustee has
been appointed and has accepted the appointment within thirty days after
notification, the retiring trustee may apply to a court of competent
jurisdiction for the appointment of a successor. In case at any time the trustee
shall not meet the requirements set forth in the trust agreement, or shall
become incapable of acting, or if a court having jurisdiction in the premises
shall enter a decree or order for relief in respect of the trustee in an
involuntary case, or the trustee shall commence a voluntary case, under any
applicable bankruptcy, insolvency or other similar law now or hereafter in
effect, or any receiver, liquidator, assignee, custodian, trustee, sequestrator
(or similar official) for the trustee or for any substantial part of its
property shall be appointed, or the trustee shall generally fail to pay its
debts as they become due, or shall fail to meet such written standards for the
trustee's performance as shall be established from time to time by the sponsor,
or if the sponsor determines in good faith that there has occurred either (1) a
material deterioration in the creditworthiness of the trustee or (2) one or more
grossly negligent acts on the part of the trustee with respect to a trust, the
sponsor, upon sixty days' prior written notice, may remove the trustee and
appoint a successor trustee, as hereinafter provided, by written instrument, in
duplicate, one copy of which shall be delivered to the trustee so removed and
one copy to the successor trustee. Notice of such removal and appointment shall
be mailed to each unitholder by the sponsor. Upon execution of a written
acceptance of such appointment by such successor trustee, all the rights,
powers, duties and obligations of the original trustee shall vest in the
successor. The trustee must be a corporation organized under the laws of the
United States, or any state thereof, be authorized under such laws to exercise
trust powers and have at all times an aggregate capital, surplus and undivided
profits of not less than $5,000,000.

THE SPONSOR. The sponsor of the trust is Advisors Asset Management, Inc.
The sponsor is a broker-dealer specializing in providing services to broker-
dealers, registered representatives, investment advisers and other financial
professionals. The sponsor's headquarters are located at 18925 Base Camp Road,
Monument, Colorado 80132. You can contact the unit investment trust division at
8100 East 22nd Street North, Building 800, Suite 102, Wichita, Kansas 67226 or
by using the contacts listed on the back cover of the prospectus. The sponsor is
a registered broker-dealer and investment adviser and a member of the Financial
Industry Regulatory Authority, Inc. (FINRA) and the Securities Investor
Protection Corporation (SIPC), and a registrant of the Municipal Securities
Rulemaking Board (MSRB).

If at any time the sponsor shall fail to perform any of its duties under
the trust agreement or shall become incapable of acting or shall be adjudged a
bankrupt or insolvent or shall have its affairs taken over by public
authorities, then the trustee may (a) appoint a successor sponsor at rates of
compensation deemed by the trustee to be reasonable and not exceeding such
reasonable amounts as may be prescribed by the Securities and Exchange
Commission, (b) terminate the

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trust agreement and liquidate any trust as provided therein, or (c) continue to
act as trustee without terminating the trust agreement.

THE EVALUATOR AND SUPERVISOR. Advisors Asset Management, Inc., the
sponsor, also serves as evaluator and supervisor. The evaluator and supervisor
may resign or be removed by the sponsor and trustee in which event the sponsor
or trustee is to use its best efforts to appoint a satisfactory successor. Such
resignation or removal shall become effective upon acceptance of appointment by
the successor evaluator. If upon resignation of the evaluator no successor has
accepted appointment within thirty days after notice of resignation, the
evaluator may apply to a court of competent jurisdiction for the appointment of
a successor. Notice of such resignation or removal and appointment shall be
mailed by the trustee to each unitholder.

LIMITATIONS ON LIABILITY. The sponsor, evaluator, and supervisor are
liable for the performance of their obligations arising from their
responsibilities under the trust agreement but will be under no liability to the
unitholders for taking any action or refraining from any action in good faith
pursuant to the trust agreement or for errors in judgment, except in cases of
its own gross negligence, bad faith or willful misconduct or its reckless
disregard for its duties thereunder. The sponsor shall not be liable or
responsible in any way for depreciation or loss incurred by reason of the sale
of any securities.

The trust agreement provides that the trustee shall be under no liability
for any action taken in good faith in reliance upon prima facie properly
executed documents or for the disposition of moneys, securities or certificates
except by reason of its own gross negligence, bad faith or willful misconduct,
or its reckless disregard for its duties under the trust agreement, nor shall
the trustee be liable or responsible in any way for depreciation or loss
incurred by reason of the sale by the trustee of any securities. In the event
that the sponsor shall fail to act, the trustee may act and shall not be liable
for any such action taken by it in good faith. The trustee shall not be
personally liable for any taxes or other governmental charges imposed upon or in
respect of the securities or upon the interest thereof. In addition, the trust
agreement contains other customary provisions limiting the liability of the
trustee.

The trustee and unitholders may rely on any evaluation furnished by the
evaluator and shall have no responsibility for the accuracy thereof. The trust
agreement provides that the determinations made by the evaluator shall be made
in good faith upon the basis of the best information available to it, provided,
however, that the evaluator shall be under no liability to the trustee or
unitholders for errors in judgment, but shall be liable for its gross
negligence, bad faith or willful misconduct or its reckless disregard for its
obligations under the trust agreement.

EXPENSES OF THE TRUST. The sponsor will not charge a trust any fees for
services performed as sponsor. The sponsor will receive a portion of the sale
commissions paid in connection with the purchase of units and will share in
profits, if any, related to the deposit of securities in the trust.

The trustee receives for its services that fee set forth in the prospectus.
The trustee's fee which is calculated and paid monthly is based on the total
number of units of the related trust outstanding as of January 1 for any annual
period, except during the initial offering period the fee

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will be based on the units outstanding at the end of each month. The trustee
benefits to the extent there are funds for future distributions, payment of
expenses and redemptions in the Capital and Income Accounts since these Accounts
are non-interest bearing and the amounts earned by the trustee are retained by
the trustee. Part of the trustee's compensation for its services to a trust is
expected to result from the use of these funds.

The supervisor will charge a trust a surveillance fee for services
performed for the trust in an amount not to exceed that amount set forth in the
prospectus but in no event will such compensation, when combined with all
compensation received from other unit investment trusts for which the sponsor
both acts as sponsor and provides portfolio surveillance, exceed the aggregate
cost to the sponsor of providing such services. Such fee shall be based on the
total number of units of the related trust outstanding as of January 1 for any
annual period, except during the initial offering period the fee will be based
on the units outstanding at the end of each month.

For evaluation of the securities in a trust, the evaluator shall receive an
evaluation fee in an amount not to exceed that amount set forth in the
prospectus but in no event will such compensation, when combined with all
compensation from other unit investment trusts for which the sponsor acts as
sponsor and provides evaluation services, exceed the aggregate cost of providing
such services. Such fee shall be based on the total number of units of the
related trust outstanding as of January 1 for any annual period, except during
the initial offering period the fee will be based on the units outstanding at
the end of each month.

For providing bookkeeping and administrative services to a trust, the
sponsor shall receive an administration fee in an amount not to exceed that
amount set forth in the prospectus but in no event will such compensation, when
combined with all compensation from other unit investment trusts for which the
sponsor acts as sponsor and provides evaluation services, exceed the aggregate
cost of providing such services. Such fee shall be based on the total number of
units of the related trust outstanding as of January 1 for any annual period,
except during the initial offering period the fee will be based on the units
outstanding at the end of each month.

Your trust will pay a license fee for the use of certain service marks,
trademarks and/or trade names of S&P.

The trustee's fee, sponsor's fee for providing bookkeeping and
administrative services to the trust, supervisor's fee and evaluator's fee are
deducted from the Income Account of the related trust to the extent funds are
available and then from the Capital Account. Each such fee (other than any
creation and development fee) may be increased without approval of unitholders
by amounts not exceeding a proportionate increase in the Consumer Price Index or
any equivalent index substituted therefor.

The following additional charges are or may be incurred by the trust:
(a) fees for the trustee's extraordinary services; (b) expenses of the trustee
(including legal and auditing expenses and reimbursement of the cost of advances
to the trust for payment of expenses and distributions, but not including any
fees and expenses charged by an agent for custody and safeguarding of
securities) and of counsel, if any; (c) various governmental charges;
(d) expenses

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and costs of any action taken by the trustee to protect the trust or the rights
and interests of the unitholders; (e) indemnification of the trustee for any
loss, liability or expense incurred by it in the administration of the trust not
resulting from negligence, bad faith or willful misconduct on its part or its
reckless disregard of its obligations under the trust agreement;
(f) indemnification of the sponsor for any loss, liability or expense incurred
in acting in that capacity without gross negligence, bad faith or willful
misconduct or its reckless disregard for its obligations under the trust
agreement; and (g) expenditures incurred in contacting unitholders upon
termination of the trust. The fees and expenses set forth herein are payable
out of a trust and, when owing to the trustee, are secured by a lien on the
trust. If the balances in the Income and Capital Accounts are insufficient to
provide for amounts payable by the trust, the trustee has the power to sell
securities to pay such amounts. These sales may result in capital gains or
losses to unitholders. A trust may pay the costs of updating its registration
statement each year.

PORTFOLIO TRANSACTIONS AND BROKERAGE ALLOCATION

When a trust sells securities, the composition and diversity of the
securities in the trust may be altered. In order to obtain the best price for a
trust, it may be necessary for the sponsor to specify minimum amounts in which
blocks of securities are to be sold. In effecting purchases and sales of a
trust's portfolio securities, the sponsor may direct that orders be placed with
and brokerage commissions be paid to brokers, including brokers which may be
affiliated with the trust, the sponsor or dealers participating in the offering
of units.

PURCHASE, REDEMPTION AND PRICING OF UNITS

PUBLIC OFFERING PRICE. Units of a trust are offered at the public offering
price thereof. During the initial offering period, the public offering price
per unit is equal to the net asset value per unit plus the applicable sales fee
referred to in the prospectus plus organization costs plus accrued interest, if
any. The initial sales fee is equal to the difference between the maximum sales
fee and the sum of the remaining deferred sales fee and the total creation and
development fee. The sales fee as a percentage of the public offering price and
the net amount invested is set forth in the prospectus. The deferred sales fee
is a fixed dollar amount and will be collected in installments as described in
the prospectus. The creation and development fee is a fixed dollar amount and
will be collected at the end of the initial offering period as described in the
prospectus. Units purchased after the initial deferred sales fee payment will
be subject to the remaining deferred sales fee payments. Units sold or redeemed
prior to such time as the entire applicable deferred sales fee has been
collected will be assessed the remaining deferred sales fee at the time of such
sale or redemption. Units sold or redeemed prior to such time as the entire
applicable creation and development fee has been collected will not be assessed
the remaining creation and development fee at the time of such sale or
redemption. During the initial offering period, a portion of the public
offering price includes an amount of securities to pay for all or a portion of
the costs incurred in establishing a trust. These costs include the cost of
preparing the registration statement, the trust indenture and other closing
documents, registering units with the Securities and Exchange Commission and
states, the initial audit of the trust portfolio, legal fees and the initial
fees and expenses of the trustee. These costs will be deducted from a trust as
of

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the end of the initial offering period or after six months, if earlier. Certain
broker-dealers may charge a transaction fee for processing unit purchases.

As indicated above, the initial public offering price of the units was
established by dividing the aggregate underlying value of the securities by the
number of units outstanding. Such price determination as of the opening of
business on the date a trust was created was made on the basis of an evaluation
of the securities in the trust prepared by the evaluator. After the opening of
business on this date, the evaluator will appraise or cause to be appraised
daily the value of the underlying securities as of the close of regular trading
on the New York Stock Exchange on days the New York Stock Exchange is open and
will adjust the public offering price of the units commensurate with such
valuation. Such public offering price will be effective for all orders received
at or prior to the close of regular trading on the New York Stock Exchange on
each such day as discussed in the prospectus. Orders received by the trustee,
sponsor or authorized financial professionals for purchases, sales or
redemptions after that time, or on a day when the New York Stock Exchange is
closed, will be held until the next determination of price as discussed in the
prospectus.

Had units of a trust been available for sale at the close of business on
the business day before the inception date of the trust, the public offering
price would have been as shown under "Essential Information" in the prospectus.
The public offering price per unit of a trust on the date of the prospectus or
on any subsequent date will vary from the amount stated under "Essential
Information" in the prospectus in accordance with fluctuations in the prices of
the underlying securities. Net asset value per unit is determined by dividing
the value of a trust's portfolio securities, cash and other assets, less all
liabilities, by the total number of units outstanding. We determine the value of
the Options in the trust's portfolio as of the close of regular trading on the
New York Stock Exchange on each day that exchange is open. We determine each
Option's value based on its good faith determination of the Option's fair value.
We will determine the value of the Options during the initial offering period
(anticipated to be only one day, the initial date of deposit) based on our good
faith determination of the fair value of the Options at our reasonable
discretion taking into consideration factors, including, but not limited to, (a)
the net amount to be paid to or received by the trust in connection with an
early termination of Options as determined pursuant to the Option agreement on
the valuation date by the Option Counterparty, (b) current ask prices for the
Options as obtained from investment dealers or brokers who customarily deal in
options comparable to the Options held by the trust and (c) ask prices for
comparable options or securities. For the Treasury Obligations, The value is
generally determined during the initial offering period based on the aggregate
offering side evaluation. After the initial offering period ends, the value of
the Treasury Obligations is generally determined based on the bid side
evaluations. The aggregate bid and offering side evaluations of the securities
shall be determined (a) on the basis of current bid or offering prices of the
securities, (b) if bid or offering prices are not available for any particular
security, on the basis of current bid or offering prices for comparable
securities, (c) by determining the value of securities on the bid or offer side
of the market by appraisal, or (d) by any combination of the above.

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The foregoing evaluations and computations shall be made as of the close of
regular trading on the New York Stock Exchange, on each business day commencing
with the trust's inception date of the securities, effective for all sales made
during the preceding 24-hour period.

The interest on the Treasury Obligations deposited in a trust, less the
related estimated fees and expenses, will accrue daily. The amount of net
interest income which accrues per unit may change as securities mature or are
redeemed, exchanged or sold, or as the expenses of a trust change or the number
of outstanding units of a trust changes.

Although payment is normally made three business days following the order
for purchase, payments may be made prior thereto. A person will become the
owner of units on the date of settlement provided payment has been received.
Cash, if any, made available to the sponsor prior to the date of settlement for
the purchase of units may be used in the sponsor's business and may be deemed to
be a benefit to the sponsor, subject to the limitations of the Securities
Exchange Act of 1934.

ACCRUED INTEREST. Accrued interest is the accumulation of unpaid interest
on a Treasury Obligation from the last day on which interest thereon was paid.
Interest on Treasury Obligations generally is paid monthly or semi-annually
although a trust accrues such interest daily. Because of this, a trust always
has an amount of interest earned but not yet collected by the trustee. For this
reason, with respect to sales settling subsequent to the first settlement date,
the public offering price of units of a trust will have added to it the
proportionate share of accrued interest to the date of settlement. Unitholders
will receive on the next distribution date of a trust the amount, if any, of
accrued interest paid on their units.

In an effort to reduce the amount of accrued interest which would otherwise
have to be paid in addition to the public offering price in the sale of units to
the public, the trustee will advance the amount of accrued interest as of the
first settlement date and the same will be distributed to the sponsor as the
unitholder of record as of the first settlement date. Consequently, the amount
of accrued interest to be added to the public offering price of units will
include only accrued interest from the first settlement date to the date of
settlement, less any distributions from the Income Account subsequent to the
first settlement date.

Because of the varying interest payment dates of securities, accrued
interest at any point in time will be greater than the amount of interest
actually received by the applicable trusts and distributed to unitholders.
Therefore, there will always remain an item of accrued interest that is added to
the value of the units. If a unitholder sells or redeems all or a portion of
his units, he will be entitled to receive his proportionate share of the accrued
interest from the purchaser of his units. Since the trustee has the use of the
funds held in the Income Account for distributions to unitholders and since such
account is non-interest-bearing to unitholders, the trustee benefits thereby.

COMPARISON OF PUBLIC OFFERING PRICE AND REDEMPTION PRICE. While the value
of Treasury Obligations for purposes of calculating the net asset value of units
during the initial offering period will generally be determined on the basis of
the current offering prices of the Treasury Obligations, after the initial
offering period the value of the Treasury Obligation for

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purposes of calculating net asset value of units will generally be determined on
the basis of the current bid prices of the Treasury Obligations. As of the
close of business on the business day before the trust's inception date, the
public offering price per unit exceeded the redemption price at which units
could have been redeemed by the amount of the sales fee. The bid prices on
Treasury Obligations similar to those in the trust are lower than the offering
prices thereof. For this reason, among others (including fluctuations in the
market prices of the securities and the fact that the public offering price
includes a sales fee), the amount realized by a unitholder upon any redemption
of units may be less than the price paid for such units.

PUBLIC DISTRIBUTION OF UNITS. The sponsor intends to qualify the units for
sale in a number of states. Units will be sold through dealers who are members
of the Financial Industry Regulatory Authority, Inc. and through others. Sales
may be made to or through dealers at prices which represent discounts from the
public offering price as set forth in the prospectus. Certain commercial banks
may be making units available to their customers on an agency basis. The
sponsor reserves the right to change the discounts from time to time.

We currently provide, at our own expense and out of our own profits,
additional compensation and benefits to broker-dealers who sell units of this
trust and our other products. This compensation is intended to result in
additional sales of our products and/or compensate broker-dealers and financial
advisors for past sales. A number of factors are considered in determining
whether to pay these additional amounts. Such factors may include, but are not
limited to, the level or type of services provided by the intermediary, the
level or expected level of sales of our products by the intermediary or its
agents, the placing of our products on a preferred or recommended product list
and access to an intermediary's personnel. We may make these payments for
marketing, promotional or related expenses, including, but not limited to,
expenses of entertaining retail customers and financial advisors, advertising,
sponsorship of events or seminars, obtaining information about the breakdown of
unit sales among an intermediary's representations or offices, obtaining shelf
space in broker-dealer firms and similar activities designed to promote the sale
of our products. We make such payments to a substantial majority of
intermediaries that sell our products. We may also make certain payments to, or
on behalf of, intermediaries to defray a portion of their costs incurred for the
purpose of facilitating unit sales, such as the costs of developing or
purchasing trading systems to process unit trades. Payments of such additional
compensation described in this paragraph and the volume concessions described
above, some of which may be characterized as "revenue sharing," may create an
incentive for financial intermediaries and their agents to sell or recommend our
products, including this trust, over other products. These arrangements will not
change the price you pay for your units. The sponsor reserves the right to
reject, in whole or in part, any order for the purchase of units.

PROFITS OF SPONSOR. The sponsor will receive gross sales fees equal to the
percentage of the offering price of the units of such trusts stated in the
prospectus and will pay a portion of such sales fees to dealers and agents. In
addition, the sponsor may realize a profit or a loss resulting from the
difference between the purchase prices of the securities to the sponsor and the
cost of such securities to a trust. The sponsor may also realize profits or
losses with respect to securities deposited in a trust which were acquired from
underwriting syndicates of which the sponsor was a member. An underwriter or
underwriting syndicate purchases securities from the issuer on a

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negotiated or competitive bid basis, as principal, with the motive of marketing
such securities to investors at a profit. The sponsor may realize additional
profits or losses during the initial offering period on unsold units as a result
of changes in the daily evaluation of the securities in a trust.

MARKET FOR UNITS. After the initial offering period, while not obligated
to do so, the sponsor may, subject to change at any time, maintain a market for
units of the trust offered hereby and to continuously offer to purchase said
units at the net asset value determined by the evaluator, provided that the
repurchase price will not be reduced by any remaining creation and development
fee or organization costs during the initial offering period. While the sponsor
may repurchase units from time to time, it does not currently intend to maintain
an active secondary market for units. Unitholders who wish to dispose of their
units should inquire of their broker as to current market prices in order to
determine whether there is in existence any price in excess of the redemption
price and, if so, the amount thereof. Unitholders who sell or redeem units
prior to such time as the entire creation and development fee on such units has
been collected will not be assessed the amount of the remaining creation and
development fee at the time of such sale or redemption. The offering price of
any units resold by the sponsor will be in accord with that described in the
currently effective prospectus describing such units. Any profit or loss
resulting from the resale of such units will belong to the sponsor. If the
sponsor decides to maintain a secondary market, it may suspend or discontinue
purchases of units of the trust if the supply of units exceeds demand, or for
other business reasons.

REDEMPTION. A unitholder who does not dispose of units in the secondary
market described above may cause units to be redeemed by the trustee by making a
written request to the trustee at its unit investment trust division office.
Unitholders must sign the request exactly as their names appear on the records
of the trustee. Additional documentation may be requested, and a signature
guarantee is always required, from corporations, executors, administrators,
trustees, guardians or associations. The signatures must be guaranteed by a
participant in the Securities Transfer Agents Medallion Program ("STAMP") or
such other signature guaranty program in addition to, or in substitution for,
STAMP, as may be accepted by the trustee.

Redemption shall be made by the trustee no later than the seventh day
following the day on which a tender for redemption is received (the "Redemption
Date") by payment of cash equivalent to the redemption price, determined as set
forth below under "Computation of Redemption Price," as of the close of regular
trading on the New York Stock Exchange next following such tender, multiplied by
the number of units being redeemed. Any units redeemed shall be canceled and
any undivided fractional interest in the related trust extinguished. The price
received upon redemption might be more or less than the amount paid by the
unitholder depending on the value of the securities in the trust at the time of
redemption. Unitholders who sell or redeem units prior to such time as the
entire deferred sales fee on such units has been collected will be assessed the
amount of the remaining deferred sales fee at the time of such sale or
redemption. Unitholders who sell or redeem units prior to such time as the
entire creation and development fee on such units has been collected will not be
assessed the amount of the remaining creation and development fee at the time of
such sale or redemption. Certain broker-dealers may charge a transaction fee
for processing redemption requests.

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Under regulations issued by the Internal Revenue Service, the trustee is
required to withhold a specified percentage of the principal amount of a unit
redemption if the trustee has not been furnished the redeeming unitholder's tax
identification number in the manner required by such regulations. Any amount so
withheld is transmitted to the Internal Revenue Service and may be recovered by
the unitholder only when filing a tax return. Under normal circumstances, the
trustee obtains the unitholder's tax identification number from the selling
broker. However, any time a unitholder elects to tender units for redemption,
such unitholder should make sure that the trustee has been provided a certified
tax identification number in order to avoid this possible "back-up withholding."
In the event the trustee has not been previously provided such number, one must
be provided at the time redemption is requested. Any amounts paid on redemption
representing interest shall be withdrawn from the Income Account of a trust to
the extent that funds are available for such purpose. All other amounts paid on
redemption shall be withdrawn from the Capital Account for a trust.

The trustee is empowered to sell securities and tender options for early
termination in order to make funds available for the redemption of units. To
the extent that securities are sold or tendered for early termination, the size
of a trust will be, and the diversity of a trust may be, reduced but each
remaining unit will continue to represent approximately the same proportional
interest in each security. Sales may be required at a time when securities
would not otherwise be sold and may result in lower prices than might otherwise
be realized. The price received upon redemption or termination may be more or
less than the amount paid by the unitholder depending on the value of the
securities in the portfolio at the time of redemption or termination.

The trustee is irrevocably authorized in its discretion, if the sponsor
does not elect to purchase any unit tendered for redemption, in lieu of
redeeming such units, to sell such units in the over-the-counter market for the
account of tendering unitholders at prices which will return to the unitholders
amounts in cash, net after brokerage commissions, transfer taxes and other
charges, equal to or in excess of the redemption price for such units. In the
event of any such sale, the trustee shall pay the net proceeds thereof to the
unitholders on the day they would otherwise be entitled to receive payment of
the redemption price.

The right of redemption may be suspended and payment postponed (1) for any
period during which the New York Stock Exchange is closed, other than customary
weekend and holiday closings, or during which (as determined by the Securities
and Exchange Commission) trading on the New York Stock Exchange is restricted;
(2) for any period during which an emergency exists as a result of which
disposal by the trustee of securities is not reasonably practicable or it is not
reasonably practicable to fairly determine the value of the underlying
securities in accordance with the trust agreement; or (3) for such other period
as the Securities and Exchange Commission may by order permit. The trustee is
not liable to any person in any way for any loss or damage which may result from
any such suspension or postponement.

COMPUTATION OF REDEMPTION PRICE. The redemption price for units of each
trust is computed by the evaluator as of the evaluation time stated in the
prospectus next occurring after the tendering of a unit for redemption and on
any other business day desired by it, by:

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A. Adding: (1) the cash on hand in the trust other than cash deposited in the
trust to purchase securities not applied to the purchase of such
securities; (2) the aggregate value of each issue of the securities held in
the trust as determined by the evaluator as described above; and (3)
interest accrued and unpaid on the securities in the trust as of the date
of computation;

B. Deducting therefrom (1) amounts representing any applicable taxes or
governmental charges payable out of the trust and for which no deductions
have been previously made for the purpose of additions to the Reserve
Account; (2) an amount representing estimated accrued expenses, including
but not limited to fees and expenses of the trustee (including legal and
auditing fees), the evaluator, the sponsor and counsel, if any; (3) cash
held for distribution to unitholders of record as of the business day prior
to the evaluation being made; and (4) other liabilities incurred by the
trust, provided that the redemption price will not be reduced by any
remaining creation and development fee or organization costs during the
initial offering period; and

C. Finally dividing the results of such computation by the number of units of
the trust outstanding as of the date thereof.

RETIREMENT PLANS. A trust may be suited for purchase by Individual
Retirement Accounts, Keogh Plans, pension funds and other qualified retirement
plans. Generally, capital gains and income received under each of the foregoing
plans are deferred from Federal taxation. All distributions from such plans are
generally treated as ordinary income but may, in some cases, be eligible for
special income averaging or tax-deferred rollover treatment. Investors
considering participation in any such plan should review specific tax laws
related thereto and should consult their attorneys or tax advisers with respect
to the establishment and maintenance of any such plan. Such plans are offered
by brokerage firms and other financial institutions. The trust will lower the
minimum investment requirement for IRA accounts. Fees and charges with respect
to such plans may vary.

OWNERSHIP OF UNITS. Ownership of units will not be evidenced by
certificates. Units may be purchased in denominations of one unit or any
multiple thereof, subject to the minimum investment requirement. Fractions of
units, if any, will be computed to three decimal places.

PERFORMANCE INFORMATION

Information contained in this Information Supplement or in the prospectus,
as it currently exists or as further updated, may also be included from time to
time in other prospectuses or in advertising material. Information on the
performance of a trust strategy or the actual performance of a trust may be
included from time to time in other prospectuses or advertising material and may
reflect sales fees and expenses of a trust. The performance of a trust may also
be compared to the performance of money managers as reported in SEI Fund
Evaluation Survey or of mutual funds as reported by Lipper Analytical Services
Inc. (which calculates total return using actual dividends on ex-dates
accumulated for the quarter and reinvested at quarter end), Money Magazine Fund
Watch (which rates fund performance over a specified time period after sales fee
and assuming all dividends reinvested) or Wiesenberger Investment Companies
Service

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(which states fund performance annually on a total return basis) or of the
New York Stock Exchange Composite Index, the American Stock Exchange Index
(unmanaged indices of stocks traded on the New York and American Stock
Exchanges, respectively), the Dow Jones Industrial Average (an index of 30
widely traded industrial common stocks) or the Standard & Poor's 500 Index (an
unmanaged diversified index of 500 stocks) or similar measurement standards
during the same period of time.

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CONTENTS OF REGISTRATION STATEMENT

This Amendment to the Registration Statement comprises the following papers
and documents:
The facing sheet
The prospectus
The signatures
The consents of the initial evaluator, independent public accountants and
legal counsel

The following exhibits:

1.1 Trust Agreement (to be filed by amendment).

1.1.1 Standard Terms and Conditions of Trust (to be filed by amendment).

1.2 Certificate of Amendment of Certificate of Incorporation and
Certificate of Merger of Advisors Asset Management, Inc. Reference is
made to Exhibit 1.2 to the Registration Statement on Form S-6 for
Advisors Disciplined Trust 647 (File No. 333-171079) as filed on
January 6, 2011.

1.3 Bylaws of Advisors Asset Management, Inc. Reference is made to
Exhibit 1.3 to the Registration Statement on Form S-6 for Advisors
Disciplined Trust 647 (File No. 333-171079) as filed on January 6, 2011.

1.5 Form of Dealer Agreement. Reference is made to Exhibit 1.5 to the
Registration Statement of Form S-6 for Advisors Disciplined Trust 262
(File No. 333-150575) as filed of June 17, 2008.

2.2 Form of Code of Ethics. Reference is made to Exhibit 2.2 to the
Registration Statement on Form S-6 for Advisor's Disciplined Trust 73
(File No. 333-131959) as filed on March 16, 2006.

3.1 Opinion of counsel as to legality of securities being registered (to be
filed by amendment).

3.2 Opinion of counsel as to New York and federal income tax status of
securities being registered (to be filed by amendment).

3.3 Opinion of counsel as to the Trustee and the Trust. (to be filed by
amendment).

4.1 Consent of evaluator (to be filed by amendment).

4.2 Consent of independent auditors (to be filed by amendment).

6.1 Directors and Officers of Advisors Asset Management, Inc. Reference is
made to Exhibit 6.1 to the Registration Statement on Form S-6 for
Advisors Disciplined Trust 1112 (File No. 333-190165) as filed on
December 11, 2013.

7.1 Power of Attorney. Reference is made to Exhibit 7.1 to the Registration
Statement on Form S-6 for Advisors Disciplined Trust 933
(File No. 333-186716) as filed on May 3, 2013.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the Registrant,
Advisors Disciplined Trust 1237 has duly caused this Amendment No. 1 to the
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Wichita and State of Kansas on June 6, 2014.

Advisors Disciplined Trust 1237

By ADVISORS ASSET MANAGEMENT, INC., DEPOSITOR

By /s/ ALEX R MEITZNER
-----------------------------
Alex R. Meitzner
Senior Vice President

Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below on June 6, 2014 by the following
persons in the capacities indicated:

SIGNATURE TITLE

Scott I. Colyer Director of Advisors Asset )
Management, Inc. )

Lisa A. Colyer Director of Advisors Asset )
Management, Inc. )

James R. Costas Director of Advisors Asset )
Management, Inc. )

Christopher T. Genovese Director of Advisors Asset )
Management, Inc. )

Randy J. Pegg Director of Advisors Asset )
Management, Inc. )

R. Scott Roberg Director of Advisors Asset )
Management, Inc. )

S-2

Jack Simkin Director of Advisors Asset )
Management, Inc. )

Andrew Williams Director of Advisors Asset )
Management, Inc. )

By /s/ ALEX R MEITZNER
-----------------------------
Alex R. Meitzner
Attorney-in-Fact*

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*An executed copy of each of the related powers of attorney is filed
herewith or incorporated herein by reference as Exhibit 7.1.

S-3