(RIVERSOURCE INVESTMENTS LOGO)

                    PROSPECTUS SUPPLEMENT -- MARCH 25, 2009*

<Table>
<Caption>

                                                                             
RiverSource Short Duration U.S. Government Fund (dated July 30, 2008)           S-6042-99 AE
</Table>



The information following the second paragraph in the Investment Manager section
has been revised as follows:

Portfolio Manager(s).  The portfolio managers responsible for the day-to-day
management of the Fund are:

Todd White, Portfolio Manager

- -   Managed the Fund since 2008.

- -   Leader of the liquid assets sector team.

- -   Joined RiverSource Investments in 2008.

- -   Managing Director, Global Head of the Asset-Backed and Mortgage-Backed
    Securities businesses, and North American Head of the Interest Rate
    business, HSBC, 2004 to 2008; Managing Director and Head of Business for
    Mortgage Pass-Through and Options, Lehman Brothers, 2000 to 2004.

- -   Began investment career in 1986.

- -   BS, Indiana University.

John G. McColley, Portfolio Manager

- -   Managed the Fund since 2009.

- -   Sector Manager, liquid assets sector team.

- -   Joined RiverSource Investments in 1985.

- -   Began investment career in 1984.

- -   BS, Carlson School of Management, University of Minnesota.

The SAI provides additional information about portfolio manager compensation,
management of other accounts and ownership of shares in the Fund.

S-6042-5 A (3/09)
* Valid until next update.



                                                  (RIVERSOURCE INVESTMENTS LOGO)

                                                             (THREADNEEDLE LOGO)

                     PROSPECTUS SUPPLEMENT -- JAN. 22, 2009*


<Table>
<Caption>
FUND                            PROSPECTUS DATE   FORM #
- --------------------------------------------------------------
                                            
RiverSource 120/20 Contrarian
  Equity Fund                   June 27, 2008     S-6519-99 C
RiverSource Absolute Return
  Currency and Income Fund      Dec. 30, 2008     S-6502-99 G
RiverSource Balanced Fund       Nov. 28, 2008     S-6326-99 AD
RiverSource California Tax-
  Exempt Fund                   Oct. 30, 2008     S-6328-99 AH
RiverSource Disciplined
  Equity Fund                   Sept. 29, 2008    S-6263-99 H
RiverSource Disciplined
  International Equity Fund     Dec. 30, 2008     S-6506-99 E
RiverSource Disciplined Large
  Cap Growth Fund               Nov. 28, 2008     S-6285-99 D
RiverSource Disciplined Large
  Cap Value Fund                Nov. 28, 2008     S-6523-99 C
RiverSource Disciplined Small
  and Mid Cap Equity Fund       Sept. 29, 2008    S-6505-99 E
RiverSource Disciplined Small
  Cap Value Fund                Sept. 29, 2008    S-6397-99 E
RiverSource Diversified Bond
  Fund                          Oct. 30, 2008     S-6495-99 AC
RiverSource Diversified
  Equity Income Fund            Nov. 28, 200      S-6475-99 AD
RiverSource Dividend
  Opportunity Fund              Aug. 29, 2008     S-6341-99 AD
RiverSource Emerging Markets
  Bond Fund                     Dec. 30, 2008     S-6398-99 E
RiverSource Equity Value Fund   May 30, 2008      S-6382-99 W
RiverSource Floating Rate
  Fund                          Sept. 29, 2008    S-6501-99 E
RiverSource Global Bond Fund    Dec. 30, 2008     S-6309-99 AE
RiverSource Global Technology
  Fund                          Dec. 30, 2008     S-6395-99 N
RiverSource Growth Fund         Sept. 29, 2008    S-6455-99 AD
RiverSource High Yield Bond
  Fund                          July 30, 2008     S-6370-99 AD
RiverSource Income Builder
  Basic Income Fund             March 31, 2008    S-6394-99 E
RiverSource Income Builder
  Enhanced Income Fund          March 31, 2008    S-6394-99 E
RiverSource Income Builder
  Moderate Income Fund          March 31, 2008    S-6394-99 E
RiverSource Income
  Opportunities Fund            Sept. 29, 2008    S-6266-99 H
RiverSource Inflation
  Protected Securities Fund     Sept. 29, 2008    S-6280-99 G
RiverSource Intermediate Tax-
  Exempt Fund                   Jan. 29, 2008     S-6355-99 T
RiverSource Large Cap Equity
  Fund                          Sept. 29, 2008    S-6244-99 J
RiverSource Large Cap Value
  Fund                          Sept. 29, 2008    S-6246-99 J
RiverSource Limited Duration
  Bond Fund                     Sept. 29, 2008    S-6265-99 H
RiverSource Mid Cap Growth
  Fund                          Jan. 29, 2008     S-6426-99 AD
RiverSource Mid Cap Value
  Fund                          Nov. 28, 2008     S-6241-99 K
RiverSource Minnesota Tax-
  Exempt Fund                   Oct. 30, 2008     S-6328-99 AH
RiverSource New York Tax-
  Exempt Fund                   Oct. 30, 2008     S-6328-99 AH
RiverSource Partners
  Aggressive Growth Fund        July 30, 2008     S-6260-99 J
RiverSource Partners
  Fundamental Value Fund        July 30, 2008     S-6236-99 L
RiverSource Partners
  International Select Growth
  Fund                          Dec. 30, 2008     S-6243-99 M
RiverSource Partners
  International Select Value
  Fund                          Dec. 30, 2008     S-6242-99 M
RiverSource Partners
  International Small Cap
  Fund                          Dec. 30, 2008     S-6258-99 K
RiverSource Partners Select
  Value Fund                    July 30, 2008     S-6240-99 K
RiverSource Partners Small
  Cap Equity Fund               July 30, 2008     S-6237-99 L
RiverSource Partners Small
  Cap Growth Fund               May 30, 2008      S-6301-99 L
RiverSource Partners Small
  Cap Value Fund                July 30, 2008     S-6239-99 L
RiverSource Portfolio Builder
  Aggressive Fund               March 31, 2008    S-6282-99 G
RiverSource Portfolio Builder
  Conservative Fund             March 31, 2008    S-6282-99 G
RiverSource Portfolio Builder
  Moderate Aggressive Fund      March 31, 2008    S-6282-99 G
RiverSource Portfolio Builder
  Moderate Conservative Fund    March 31, 2008    S-6282-99 G
RiverSource Portfolio Builder
  Moderate Fund                 March 31, 2008    S-6282-99 G
RiverSource Portfolio Builder
  Total Equity Fund             March 31, 2008    S-6282-99 G
RiverSource Precious Metals
  and Mining Fund               May 30, 2008      S-6142-99 AE
RiverSource Real Estate Fund    Aug. 29, 2008     S-6281-99 G
RiverSource Retirement Plus
  2010 Fund                     June 27, 2008     S-6507-99 E
RiverSource Retirement Plus
  2015 Fund                     June 27, 2008     S-6507-99 E
RiverSource Retirement Plus
  2020 Fund                     June 27, 2008     S-6507-99 E
RiverSource Retirement Plus
  2025 Fund                     June 27, 2008     S-6507-99 E
RiverSource Retirement Plus
  2030 Fund                     June 27, 2008     S-6507-99 E
RiverSource Retirement Plus
  2035 Fund                     June 27, 2008     S-6507-99 E
RiverSource Retirement Plus
  2040 Fund                     June 27, 2008     S-6507-99 E
RiverSource Retirement Plus
  2045 Fund                     June 27, 2008     S-6507-99 E
RiverSource Short Duration
  U.S. Government Fund          July 30, 2008     S-6042-99 AE
RiverSource Small Cap
  Advantage Fund                May 30, 2008      S-6427-99 N
RiverSource Small Company
  Index Fund                    March 31, 2008    S-6357-99 U
RiverSource Strategic
  Allocation Fund               Nov. 28, 2008     S-6141-99 AE
RiverSource Strategic Income
  Allocation Fund               Nov. 28, 2008     S-6287-99 D
RiverSource Tax-Exempt Bond
  Fund                          Jan. 29, 2008     S-6310-99 AE
RiverSource Tax-Exempt High
  Income Fund                   Jan. 29, 2008     S-6430-99 AE
RiverSource U.S. Government
  Mortgage Fund                 July 30, 2008     S-6245-99 K
Threadneedle Emerging Markets
  Fund                          Dec. 30, 2008     S-6354-99 V
Threadneedle European Equity
  Fund                          Dec. 30, 2008     S-6006-99 N
Threadneedle Global Equity
  Fund                          Dec. 30, 2008     S-6334-99 AG
Threadneedle Global Equity
  Income Fund                   Dec. 30, 2008     S-6334-99 AG
Threadneedle Global Extended
  Alpha Fund                    Dec. 30, 2008     S-6334-99 AG
Threadneedle International
  Opportunity Fund              Dec. 30, 2008     S-6140-99 AG
</Table>



- --------------------------------------------------------------------------------
S-6141-10 A (1/09)
* Valid until Dec. 30, 2009



Effective February 9, 2009, the section of prospectus "Initial Sales
Charge -- Waiver of the sales charge for Class A shares" is replaced with the
following:

INITIAL SALES CHARGE -- WAIVERS OF THE SALES CHARGE FOR CLASS A SHARES. Sales
charges do not apply to:
     - current or retired Board members, officers or employees of the funds or
       RiverSource Investments or its affiliates, their spouses or domestic
       partners, children, parents and their spouse's or domestic partner's
       parents.
     - current or retired Ameriprise Financial Services, Inc. financial
       advisors, employees of financial advisors, their spouses or domestic
       partners, children, parents and their spouse's or domestic partner's
       parents.
     - registered representatives and other employees of financial institutions
       having a selling agreement with the distributor, including their spouses,
       domestic partners, children, parents and their spouse's or domestic
       partner's parents.
     - portfolio managers employed by subadvisers of the funds, including their
       spouses or domestic partners, children, parents and their spouse's or
       domestic partner's parents.
     - partners and employees of outside legal counsel to the funds or the
       funds' directors or trustees who regularly provide advice and services to
       the funds, or to their directors or trustees.
     - direct rollovers from qualified employee benefit plans, provided that the
       rollover involves a transfer to Class A shares in the same fund.
     - purchases made:
       - with dividend or capital gain distributions from a fund or from the
         same class of another fund in the RiverSource complex of funds;
       - through or under a wrap fee product or other investment product
         sponsored by a financial intermediary that charges an account
         management fee that has, or clears trades through a financial
         intermediary that has, a selling agreement with the distributor;
       - through state sponsored college savings plans established under Section
         529 of the Internal Revenue Code;
       - through bank trust departments.
     - purchases made through "eligible employee benefit plans" created under
       section 401(a), 401(k), 457 and 403(b) which:
       - have at least $1 million in plan assets at the time of investment;
       - have a plan level or omnibus account that is maintained with the fund
         or its transfer agent; and
       - transact directly with the fund or its transfer agent through a third
         party administrator or third party recordkeeper.

For more information regarding waivers of sales charges for Class A purchases,
please see the SAI.

The distributor may, in its sole discretion, authorize the waiver of sales
charges for additional purchases or categories of purchases. Policies related to
reducing or waiving the sales charge may be modified or withdrawn at any time.

Unless you provide your financial intermediary with information in writing about
all of the factors that may count toward a waiver of the sales charge, there can
be no assurance that you will receive all of the waivers for which you may be
eligible. You should request that your financial intermediary provide this
information to the fund when placing your purchase order.

Because the current prospectus is available on the funds' website at
riversource.com free of charge, information regarding breakpoint discounts is
not separately disclosed on the website.

S-6141-10 A (1/09)
* Valid until Dec. 30, 2009



                                                  (RIVERSOURCE INVESTMENTS LOGO)

                     PROSPECTUS SUPPLEMENT -- NOV. 28, 2008

<Table>
<Caption>
Fund                                                             Prospectus date           Form #
                                                                                  
RiverSource Short Duration U.S. Government Fund                    July 30, 2008        S-6042-99 AE
</Table>



Effective Nov. 17, 2008, the information following the second paragraph in the
Investment Manager section has been revised to state:

Portfolio Manager(s).  The portfolio managers responsible for the day-to-day
management of the Fund are:

Jamie Jackson, CFA, Portfolio Manager

- -   Managed the Fund since 2003.

- -   Leader of the liquid assets sector team.

- -   Joined RiverSource Investments in 2003.

- -   Co-head of U.S. Investment Grade Fixed Income, UBS Global Asset Management,
    1997 to 2003.

- -   Began investment career in 1988.

- -   MBA, Marquette University.

Todd White, Portfolio Manager

- -   Managed the Fund since 2008.

- -   Leader of the structured assets sector team.

- -   Joined RiverSource Investments in 2008.

- -   Managing Director, Global Head of the Asset-Backed and Mortgage-Backed
    Securities businesses, and North American Head of the Interest Rate
    business, HSBC, 2004 to 2008; Managing Director and Head of Business for
    Mortgage Pass-Through and Options, Lehman Brothers, 2000 to 2004.

- -   Began investment career in 1986.

- -   BS, Indiana University.

The SAI provides additional information about portfolio manager compensation,
management of other accounts and ownership of shares in the Fund.

S-6042-4 A (11/08)



                                                  (RIVERSOURCE INVESTMENTS LOGO)

                                                             (THREADNEEDLE LOGO)

                      PROSPECTUS SUPPLEMENT -- NOV. 7, 2008




FUND (Prospectus Date)                  FORM #
- ----------------------------------------------------
                                     
RIVERSOURCE 120/20 CONTRARIAN EQUITY
  FUND (6/27/08)                        S-6502-99 F
RIVERSOURCE 130/30 U.S. EQUITY FUND
  (6/27/08)                             S-6502-99 F
RIVERSOURCE ABSOLUTE
  RETURN CURRENCY AND INCOME FUND
  (6/27/08)                             S-6502-99 F
RIVERSOURCE BALANCED FUND (11/29/07)    S-6326-99 AC
RIVERSOURCE CALIFORNIA TAX-EXEMPT FUND
  (10/30/08)                            S-6328-99 AH
RIVERSOURCE CASH MANAGEMENT FUND
  (9/29/08)                             S-6320-99 AF
RIVERSOURCE DISCIPLINED EQUITY FUND
  (9/29/08)                             S-6263-99 H
RIVERSOURCE DISCIPLINED
  INTERNATIONAL EQUITY FUND (12/28/07)  S-6506-99 D
RIVERSOURCE DISCIPLINED
  LARGE CAP GROWTH FUND (11/29/07)      S-6285-99 C
RIVERSOURCE DISCIPLINED LARGE CAP
  VALUE FUND (8/1/08)                   S-6523-99 A
RIVERSOURCE DISCIPLINED
  SMALL AND MID CAP EQUITY FUND
  (9/29/08)                             S-6505-99 E
RIVERSOURCE DISCIPLINED SMALL CAP
  VALUE FUND (9/29/08)                  S-6397-99 E
RIVERSOURCE DIVERSIFIED BOND FUND
  (10/30/08)                            S-6495-99 AC
RIVERSOURCE DIVERSIFIED EQUITY INCOME
  FUND (11/29/07)                       S-6475-99 AC
RIVERSOURCE DIVIDEND OPPORTUNITY FUND
  (8/29/08)                             S-6341-99 AD
RIVERSOURCE EMERGING MARKETS BOND FUND
  (12/28/07)                            S-6398-99 D
RIVERSOURCE EQUITY VALUE FUND
  (5/30/08)                             S-6382-99 W
RIVERSOURCE FLOATING RATE FUND
  (9/29/08)                             S-6501-99 E
RIVERSOURCE GLOBAL BOND FUND
  (12/28/07)                            S-6309-99 AD
RIVERSOURCE GLOBAL TECHNOLOGY FUND
  (12/28/07)                            S-6395-99 M
RIVERSOURCE GROWTH FUND (9/29/08)       S-6455-99 AD
RIVERSOURCE HIGH YIELD BOND FUND
  (7/30/08)                             S-6370-99 AD
RIVERSOURCE INCOME BUILDER BASIC
  INCOME FUND (3/31/08)                 S-6394-99 E
RIVERSOURCE INCOME
  BUILDER ENHANCED INCOME FUND
  (3/31/08)                             S-6394-99 E
RIVERSOURCE INCOME
  BUILDER MODERATE INCOME FUND
  (3/31/08)                             S-6394-99 E
RIVERSOURCE INCOME OPPORTUNITIES FUND
  (9/29/08)                             S-6266-99 H
RIVERSOURCE INFLATION PROTECTED
  SECURITIES FUND (9/29/08)             S-6280-99 G
RIVERSOURCE INTERMEDIATE TAX-EXEMPT
  FUND (1/29/08)                        S-6355-99 T
RIVERSOURCE LARGE CAP EQUITY FUND
  (9/29/08)                             S-6244-99 J
RIVERSOURCE LARGE CAP VALUE FUND
  (9/29/08)                             S-6246-99 J
RIVERSOURCE LIMITED DURATION BOND FUND
  (9/29/08)                             S-6265-99 H
RIVERSOURCE MID CAP GROWTH FUND
  (1/29/08)                             S-6426-99 AD
RIVERSOURCE MID CAP VALUE FUND
  (11/29/07)                            S-6241-99 J
RIVERSOURCE MINNESOTA TAX-EXEMPT FUND
  (10/30/08)                            S-6328-99 AH
RIVERSOURCE NEW YORK TAX-EXEMPT FUND
  (10/30/08)                            S-6328-99 AH
RIVERSOURCE PARTNERS AGGRESSIVE GROWTH
  FUND (7/30/08)                        S-6260-99 J
RIVERSOURCE PARTNERS FUNDAMENTAL VALUE
  FUND (7/30/08)                        S-6236-99 L
RIVERSOURCE PARTNERS INTERNATIONAL
  SELECT GROWTH FUND (12/28/07)         S-6243-99 L
RIVERSOURCE PARTNERS INTERNATIONAL
  SELECT VALUE FUND (12/28/07)          S-6242-99 L
RIVERSOURCE PARTNERS INTERNATIONAL
  SMALL CAP FUND (12/28/07)             S-6258-99 J
RIVERSOURCE PARTNERS SELECT VALUE FUND
  (7/30/08)                             S-6240-99 K
RIVERSOURCE PARTNERS SMALL CAP EQUITY
  FUND (7/30/08)                        S-6237-99 L
RIVERSOURCE PARTNERS SMALL CAP GROWTH
  FUND (5/30/08)                        S-6301-99 L
RIVERSOURCE PARTNERS SMALL CAP VALUE
  FUND (7/30/08)                        S-6239-99 L
RIVERSOURCE PORTFOLIO BUILDER
  AGGRESSIVE FUND (3/31/08)             S-6282-99 G
RIVERSOURCE PORTFOLIO BUILDER
  CONSERVATIVE FUND (3/31/08)           S-6282-99 G
RIVERSOURCE PORTFOLIO BUILDER
  MODERATE AGGRESSIVE FUND (3/31/08)    S-6282-99 G
RIVERSOURCE PORTFOLIO BUILDER
  MODERATE CONSERVATIVE FUND (3/31/08)  S-6282-99 G
RIVERSOURCE PORTFOLIO BUILDER MODERATE
  FUND (3/31/08)                        S-6282-99 G
RIVERSOURCE PORTFOLIO BUILDER
  TOTAL EQUITY FUND (3/31/08)           S-6282-99 G
RIVERSOURCE PRECIOUS METALS AND MINING
  FUND (5/30/08)                        S-6142-99 AE
RIVERSOURCE REAL ESTATE FUND (8/29/08)  S-6281-99 G
RIVERSOURCE RETIREMENT PLUS 2010 FUND
  (6/27/08)                             S-6507-99 E
RIVERSOURCE RETIREMENT PLUS 2015 FUND
  (6/27/08)                             S-6507-99 E
RIVERSOURCE RETIREMENT PLUS 2020 FUND
  (6/27/08)                             S-6507-99 E
RIVERSOURCE RETIREMENT PLUS 2025 FUND
  (6/27/08)                             S-6507-99 E
RIVERSOURCE RETIREMENT PLUS 2030 FUND
  (6/27/08)                             S-6507-99 E
RIVERSOURCE RETIREMENT PLUS 2035 FUND
  (6/27/08)                             S-6507-99 E
RIVERSOURCE RETIREMENT PLUS 2040 FUND
  (6/27/08)                             S-6507-99 E
RIVERSOURCE RETIREMENT PLUS 2045 FUND
  (6/27/08)                             S-6507-99 E
RIVERSOURCE S&P 500 INDEX FUND
  (3/31/08)                             S-6434-99 N
RIVERSOURCE SHORT DURATION
  U.S. GOVERNMENT FUND (7/30/08)        S-6042-99 AE
RIVERSOURCE SMALL CAP ADVANTAGE FUND
  (5/30/08)                             S-6427-99 N
RIVERSOURCE SMALL COMPANY INDEX FUND
  (3/31/08)                             S-6357-99 U
RIVERSOURCE STRATEGIC ALLOCATION FUND
  (11/29/07)                            S-6141-99 AD
RIVERSOURCE STRATEGIC INCOME
  ALLOCATION FUND (11/29/07)            S-6287-99 C
RIVERSOURCE TAX-EXEMPT BOND FUND
  (1/29/08)                             S-6310-99 AE
RIVERSOURCE TAX-EXEMPT HIGH INCOME
  FUND (1/29/08)                        S-6430-99 AE
RIVERSOURCE TAX-EXEMPT MONEY MARKET
  FUND (2/29/08)                        S-6433-99 AE
RIVERSOURCE U.S. GOVERNMENT MORTGAGE
  FUND (7/30/08)                        S-6245-99 K
THREADNEEDLE
  EMERGING MARKETS FUND (12/28/07,
  amended 3/31/08)                      S-6354-99 U
THREADNEEDLE EUROPEAN
  EQUITY FUND (12/28/07, amended
  3/31/08)                              S-6006-99 M
THREADNEEDLE GLOBAL EQUITY FUND
  (8/1/08)                              S-6334-99 AF
THREADNEEDLE GLOBAL EQUITY INCOME FUND
  (8/1/08)                              S-6334-99 AF
THREADNEEDLE GLOBAL EXTENDED ALPHA
  FUND (8/1/08)                         S-6334-99 AF
THREADNEEDLE INTERNATIONAL
  OPPORTUNITY FUND (12/28/07, amended
  3/31/08)                              S-6140-99 AF




Effective November 7, 2008, RiverSource Investments, LLC, investment manager to
the RiverSource complex of funds, and a wholly owned subsidiary of Ameriprise
Financial, Inc., announced the closing of its acquisition of J. & W. Seligman &
Co. Incorporated ("Seligman Investments"). Seligman Investments served as
investment manager to the Seligman group of funds.

The RiverSource Complex of Funds disclosure on the Table of Contents page is
revised as follows:

RIVERSOURCE COMPLEX OF FUNDS

The RiverSource complex of funds includes a comprehensive array of funds from
RiverSource Investments, including several Seligman funds. RiverSource
Investments has also partnered with a number of professional investment
managers, including its affiliate, Threadneedle Investments, to expand the array
of funds offered in the RiverSource complex. RiverSource funds, RiverSource
Partners funds and Threadneedle funds share the same Board of Directors/Trustees
(the Board), and the same policies and procedures including those set forth in
the service section. Although the Seligman funds share the same Board, they do
not currently have the same policies and procedures, and may not be exchanged
for shares of the RiverSource funds, RiverSource Partners funds or Threadneedle
funds. Please see the Statement of Additional Information (SAI) for a complete
list of mutual funds included in the RiverSource complex of funds.

RiverSource Variable Portfolio Funds and Seligman (Variable) Portfolio Funds are
sold exclusively as underlying investment options of variable insurance policies
and annuity contracts offered by affiliated and unaffiliated insurance
companies.

The first paragraph in the "Investment Manager" section is revised as follows:

RiverSource Investments, LLC (the investment manager or RiverSource
Investments), 200 Ameriprise Financial Center, Minneapolis, Minnesota 55474, is
the investment manager to the RiverSource funds (including the RiverSource
Partners funds, Threadneedle funds and Seligman funds), and is a wholly-owned
subsidiary of Ameriprise Financial, Inc. (Ameriprise Financial). Ameriprise
Financial is a financial planning and financial services company that has been
offering solutions for clients' asset accumulation, income management and
protection needs for more than 110 years. In addition to managing investments
for all of the RiverSource funds, RiverSource Investments manages investments
for itself and its affiliates. For institutional clients, RiverSource
Investments and its affiliates provide investment management and related
services, such as separate account asset management, and institutional trust and
custody, as well as other investment products. For all of its clients,
RiverSource Investments seeks to allocate investment opportunities in an
equitable manner over time. See the SAI for more information.

The RiverSource Complex of Funds disclosure in the "Buying and Selling Shares"
section is revised as follows:

RIVERSOURCE COMPLEX OF FUNDS

THE RIVERSOURCE COMPLEX OF FUNDS INCLUDES "RIVERSOURCE" FUNDS, "RIVERSOURCE
PARTNERS" FUNDS, AND "THREADNEEDLE" FUNDS (EACH INDIVIDUALLY A "FUND" OR A
"RIVERSOURCE FUND" AND COLLECTIVELY THE "FUNDS" OR THE "RIVERSOURCE FUNDS"). THE
RIVERSOURCE COMPLEX OF FUNDS ALSO INCLUDES "SELIGMAN" FUNDS. THE RIVERSOURCE
FUNDS AND THE SELIGMAN FUNDS SHARE THE SAME BOARD OF DIRECTORS/TRUSTEES (THE
"BOARD"), BUT INVESTORS MAY NOT CURRENTLY MAKE EXCHANGES BETWEEN THE SELIGMAN
FUNDS AND THE RIVERSOURCE FUNDS. SELIGMAN FUNDS GENERALLY HAVE SEPARATE AND
DISTINCT POLICIES AND PROCEDURES FROM THE RIVERSOURCE FUNDS. THE RIVERSOURCE
FUNDS SHARE THE SAME POLICIES AND PROCEDURES INCLUDING THOSE SET FORTH IN THIS
SERVICE SECTION OF THIS PROSPECTUS. FOR EXAMPLE, FOR PURPOSES OF CALCULATING THE
INITIAL SALES CHARGE ON THE PURCHASE OF CLASS A SHARES OF A RIVERSOURCE FUND, AN
INVESTOR OR FINANCIAL ADVISOR SHOULD CONSIDER THE COMBINED MARKET VALUE OF ALL
RIVERSOURCE FUNDS (INCLUDING "THREADNEEDLE" OR "RIVERSOURCE PARTNERS" FUNDS),
OWNED BY THE INVESTOR AS DEFINED UNDER "INITIAL SALES CHARGE -- RIGHTS OF
ACCUMULATION (ROA)." AN INVESTOR OR FINANCIAL ADVISOR MAY NOT INCLUDE THE MARKET
VALUE OF ANY SELIGMAN FUNDS OWNED BY THE INVESTOR IN THIS CALCULATION.

FOR ALL FUNDS EXCEPT RIVERSOURCE CASH MANAGEMENT FUND, RIVERSOURCE S&P 500 INDEX
FUND AND RIVERSOURCE TAX-EXEMPT MONEY MARKET FUND: Effective Dec. 1, 2008, the
"Investment Options Summary" table in the "Buying and Selling Shares" section is
revised as follows:

INVESTMENT OPTIONS SUMMARY

<Table>
<Caption>
                                                             CONTINGENT                                         PLAN
                                  INITIAL SALES              DEFERRED SALES             DISTRIBUTION AND        ADMINISTRATION
                AVAILABILITY(a)   CHARGE                     CHARGE (CDSC)              SERVICE FEE(b)          FEE
- ----------------------------------------------------------------------------------------------------------------------------------
                                                                                                 
Class A         Available to all  Yes. Payable at time of    No.(c)                     Yes.                    No.
                investors.        purchase.  Lower or no                                0.25%
                                  sales charge for larger
                                  investments.
- ----------------------------------------------------------------------------------------------------------------------------------

Class B(d),(e)  Available to all  No. Entire purchase price  Maximum 5% CDSC during     Yes.                    No.
                investors.        is invested in shares of   the first year decreasing  1.00%
                                  the fund.                  to 0% after six years.
- ----------------------------------------------------------------------------------------------------------------------------------

Class C         Available to all  No. Entire purchase price  1% CSDC may apply if you   Yes.                    No.
                investors.        is invested in shares of   sell shares within one     1.00%
                                  the fund.                  year after purchase.
- ----------------------------------------------------------------------------------------------------------------------------------

</Table>



<Table>
<Caption>
                                                             CONTINGENT                                         PLAN
                                  INITIAL SALES              DEFERRED SALES             DISTRIBUTION AND        ADMINISTRATION
                AVAILABILITY(a)   CHARGE                     CHARGE (CDSC)              SERVICE FEE(b)          FEE
- ----------------------------------------------------------------------------------------------------------------------------------
                                                                                                 
Class I         Limited to        No.                        No.                        No.                     No.
                qualifying
                investors.
- ----------------------------------------------------------------------------------------------------------------------------------

Class R2        Limited to        No.                        No.                        Yes.                    Yes.
                qualifying                                                              0.50%                   0.25%
                investors.
- ----------------------------------------------------------------------------------------------------------------------------------

Class R3        Limited to        No.                        No.                        Yes.                    Yes.
                qualifying                                                              0.25%                   0.25%
                investors.
- ----------------------------------------------------------------------------------------------------------------------------------

Class R4        Limited to        No.                        No.                        No.                     Yes.
                qualifying                                                                                      0.25%
                investors.
- ----------------------------------------------------------------------------------------------------------------------------------

Class R5        Limited to        No.                        No.                        No.                     No.
                qualifying
                investors.
- ----------------------------------------------------------------------------------------------------------------------------------

Class W         Limited to        No.                        No.                        Yes.                    No.
                qualifying                                                              0.25%
                discretionary
                managed
                accounts.
- ----------------------------------------------------------------------------------------------------------------------------------
</Table>



  (a)    See "Buying and Selling Shares, Determining which class of shares to
         purchase" for more information on availability of share classes and
         eligible investors. See "Buying and Selling Shares, Opening an Account"
         for information on minimum investment and account balance requirements.
  (b)    For each of Class A, Class B, Class C, Class R2, Class R3 and Class W
         shares, as applicable, each fund has adopted a plan under Rule 12b-1 of
         the Investment Company Act of 1940, as amended, that allows it to pay
         distribution and shareholder servicing-related expenses for the sale of
         shares and the servicing of shareholders. This plan has been reviewed
         and approved by the Board. Because these fees are paid out of fund
         assets on an on-going basis, over time these fees will increase the
         cost of your investment and may cost you more than paying other types
         of distribution (sales) or servicing charges.
  (c)    A 1% CDSC may be accessed on Class A shares sold within 18 months after
         purchase. See "Buying and Selling Shares, Sales Charges, Class
         A -- contingent deferred sales charge" for more information.
  (d)    See "Buying and Selling Shares, Sales Charges, Class B and Class
         C -- contingent deferred sales charge alternative" for more information
         on the timing of conversion of Class B shares to Class A shares. Timing
         of conversion will vary depending on the date of your original purchase
         of the Class B shares.
  (e)    Class B shares of each of RiverSource Floating Rate Fund, RiverSource
         Inflation Protected Securities Fund, RiverSource Intermediate Tax-
         Exempt Fund, RiverSource Limited Duration Bond Fund and RiverSource
         Short Duration U.S. Government Fund are closed to new investors and new
         purchases. (Existing shareholders in these funds may continue to own
         Class B shares and make exchanges into and out of existing accounts
         where Class B shares of these funds are maintained.) Class B shares of
         RiverSource Absolute Return Currency and Income Fund are only available
         for exchanges from Class B shares of another RiverSource fund.

FOR ALL FUNDS EXCEPT RIVERSOURCE CASH MANAGEMENT FUND, RIVERSOURCE S&P 500 INDEX
FUND AND RIVERSOURCE TAX-EXEMPT MONEY MARKET FUND: Effective Dec. 1, 2008, the
following information is added after the section "Sales Charges -- Initial Sales
Charge -- Waivers of the sales charge for Class A shares":

CLASS A -- CONTINGENT DEFERRED SALES CHARGE

For Class A shares purchased after Dec. 1, 2008 without a sales charge, a 1%
CDSC may be charged if you sell your shares within 18 months after purchase. A
CDSC will be based on the original purchase cost or the current market value of
the shares being sold, whichever is less.

CDSC -- WAIVERS OF THE CDSC FOR CLASS A SHARES. The CDSC will be waived on sales
of shares:

     - To which no sales commission or transaction fee was paid to an authorized
       financial institution at the time of purchase.
     - Purchased through reinvestment of dividends and capital gain
       distributions.
     - In the event of the shareholder's death.
     - From a monthly, quarterly or annual systematic redemption plan of up to
       an annual amount of 12% of the account value on a per fund basis.
     - In an account that has been closed because it falls below the minimum
       account balance.
     - That result in mandatory withdrawals from an ERISA plan of a shareholder
       who is at least 70 1/2 years old.
     - That result from returns of excess contributions or excess deferral
       amounts made to a retirement plan participant.
     - Purchased prior to Dec. 1, 2008.

The distributor may, in its sole discretion, authorize the waiver of the CDSC
for additional purchases or categories of purchases. Policies relating to
waiving the CDSC may be modified or withdrawn at any time.

The following information is added to the section "Exchanges -- Other exchange
policies":

     - If your shares are subject to a CDSC, you will not be charged a CDSC upon
       the exchange of those shares. Any CDSC will be deducted when you sell the
       shares you received from the exchange. The CDSC imposed at that time will
       be based on the period that begins when you bought shares of the original
       fund and ends when you sell the shares of the fund you exchanged to.



FOR ALL FUNDS EXCEPT RIVERSOURCE S&P 500 INDEX FUND: Effective Nov. 21, 2008,
the Repurchases paragraph in the "Selling Shares" section is revised as follows:

REPURCHASES. You can change your mind after requesting a sale of shares and use
all or part of the sale proceeds to purchase new shares of RiverSource funds. If
your original purchase was in Class A or Class B, you may use all or part of the
sale proceeds to purchase new Class A shares in any RiverSource fund account
linked together for ROA purposes. Your repurchase will be in Class A shares at
NAV, up to the amount of the sale proceeds. Repurchases of Class B shares will
also be in Class A shares at NAV. Any CDSC paid upon redemption of your Class B
shares will not be reimbursed. If your original purchase was in Class C, you
will be allowed to reinvest in the same Class C account and fund you originally
purchased. In a Class C repurchase, the CDSC you paid will be reinvested and the
shares will be deemed to have the original cost and purchase date for purposes
of applying the CDSC (if any) to subsequent redemptions. Systematic withdrawals
and purchases will be excluded from this policy.

In order for you to take advantage of this repurchase waiver, you must notify
your financial institution within 90 days of the date your sale request was
processed. Contact your financial institution for information on required
documentation. The repurchase privilege may be modified or discontinued at any
time and use of this option may have tax consequences.

The following paragraph in the "Additional Services and Compensation" section is
revised as follows:

Distribution and Shareholder Services.  RiverSource Distributors, Inc., 50611
Ameriprise Financial Center, Minneapolis, Minnesota 55474, and Seligman
Advisors, Inc., 100 Park Avenue, New York, New York 10017, (collectively, the
distributor), provide underwriting and distribution services to the RiverSource
funds. Under the Distribution Agreement and related distribution and shareholder
servicing plans, the distributor receives distribution and shareholder servicing
fees. The distributor may retain a portion of these fees to support its
distribution and shareholder servicing activity. The distributor reallows the
remainder of these fees (or the full fee) to the financial institutions that
sell fund shares and provide services to shareholders. Fees paid by a fund for
these services are set forth under "Distribution and/or service (12b-1) fees" in
the expense table under "Fees and Expenses." More information on how these fees
are used is set forth under "Investment Options -- Classes of Shares" and in the
SAI. The distributor also administers any sales charges paid by an investor at
the time of purchase or at the time of sale. See "Shareholder Fees (fees paid
directly from your investment)" under "Fees and Expenses" for the scheduled
sales charge of each share class. See "Buying and Selling Shares, Sales Charges"
for variations in the scheduled sales charges, and for how these sales charges
are used by the distributor. See "Other Investment Strategies and Risks" for the
RiverSource funds' policy regarding directed brokerage.

S-6495-10 A (11/08)



Prospectus

                                                  (RIVERSOURCE INVESTMENTS LOGO)

RIVERSOURCE

SHORT DURATION U.S. GOVERNMENT FUND

PROSPECTUS JULY 30, 2008
RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND SEEKS TO PROVIDE SHAREHOLDERS
WITH A HIGH LEVEL OF CURRENT INCOME AND SAFETY OF PRINCIPAL CONSISTENT WITH
INVESTMENT IN U.S. GOVERNMENT AND GOVERNMENT AGENCY SECURITIES.

Classes A, B, C, I, R4 and W

As with all mutual funds, the Securities and
Exchange Commission has not approved or
disapproved these securities or passed upon the
adequacy of this prospectus.
Any representation to the contrary is a criminal
offense.

You may qualify for sales charge discounts on purchases of Class A
shares. Please notify your financial institution if you have other
accounts holding shares of RiverSource funds to determine whether
you qualify for a sales charge discount. See "Buying and Selling
Shares" for more information.

 NOT FDIC INSURED - MAY LOSE VALUE - NO BANK GUARANTEE


TABLE OF CONTENTS

<Table>
                                                             
THE FUND....................................................      3P
Objective...................................................      3p
Principal Investment Strategies.............................      3p
Principal Risks.............................................      4p
Past Performance............................................      6p
Fees and Expenses...........................................     10p
Other Investment Strategies and Risks.......................     12p
Fund Management and Compensation............................     13p
FINANCIAL HIGHLIGHTS........................................     15P
BUYING AND SELLING SHARES...................................     S.1
Description of Share Classes................................     S.2
   Investment Options -- Classes of Shares .................     S.2
   Sales Charges............................................     S.6
   Opening an Account.......................................    S.12
Exchanging or Selling Shares................................    S.15
   Exchanges................................................    S.17
   Selling Shares...........................................    S.19
VALUING FUND SHARES.........................................    S.20
DISTRIBUTIONS AND TAXES.....................................    S.21
GENERAL INFORMATION.........................................    S.24
</Table>

RIVERSOURCE COMPLEX OF FUNDS

The RiverSource complex of funds includes funds branded "RiverSource,"
"RiverSource Partners," and "Threadneedle." These funds share the same Board of
Directors/Trustees, and the same policies and procedures including those set
forth in the service section. RiverSource Variable Portfolio Funds are sold
exclusively as underlying investment options of variable insurance policies and
annuity contracts offered by affiliated insurance companies. Please see the
Statement of Additional Information (SAI) for a complete list of mutual funds
included in the RiverSource complex of funds.

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

2P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


THE FUND

OBJECTIVE

RiverSource Short Duration U.S. Government Fund (the Fund) seeks to provide
shareholders with a high level of current income and safety of principal
consistent with investment in U.S. government and government agency securities.
Because any investment involves risk, there is no assurance these objectives can
be achieved. Only shareholders can change the Fund's objectives.

PRINCIPAL INVESTMENT STRATEGIES

Under normal market conditions, at least 80% of the Fund's net assets are
invested in debt securities issued or guaranteed as to principal and interest by
the U.S. government, or its agencies or instrumentalities. Shareholders will be
given at least 60 days' notice of any change in the 80% policy. The Fund invests
in direct obligations of the U.S. government, such as Treasury bonds, bills, and
notes, and of its agencies and instrumentalities. The Fund may invest to a
substantial degree in securities issued by various entities sponsored by the
U.S. government, such as the Federal National Mortgage Association (FNMA or
Fannie Mae) and the Federal Home Loan Mortgage Corporation (FHLMC or Freddie
Mac). These issuers are chartered or sponsored by acts of Congress; however,
their securities are neither issued nor guaranteed by the United States
Treasury. When market conditions are favorable, the Fund may also invest in debt
securities that are not issued by the U.S. government, its agencies or
instrumentalities, or that are denominated in currencies other than the U.S.
dollar.

In pursuit of the Fund's objectives, the investment manager (RiverSource
Investments, LLC) chooses investments by:

- - Reviewing credit characteristics and the interest rate outlook.

- - Identifying and buying securities that are high quality or have similar
  qualities, in the investment manager's opinion, even though they are not rated
  or have been given a lower rating by a rating agency.

Under normal market conditions, the Fund will seek to maintain an average
portfolio duration of one to three years. Duration measures the sensitivity of
bond prices to changes in interest rates. The longer the duration of a bond, the
longer it will take to repay the principal and interest obligations and the more
sensitive it will be to changes in interest rates. For example, a three year
duration means a bond is expected to decrease in value by 3% if interest rates
rise 1% and increase in value by 3% if interest rates fall 1%.

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

           RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 3P


In evaluating whether to sell a security, the investment manager considers,
among other factors, whether:

- - The security is overvalued relative to alternative investments.

- - The investment manager wishes to lock-in profits.

- - Changes in the interest rate or economic outlook.

- - The investment manager identifies a more attractive opportunity.

The investment manager may use derivatives such as futures, options, forward
contracts and swaps, including credit default swaps, in an effort to produce
incremental earnings, to hedge existing positions, to increase market exposure
and investment flexibility, or to obtain or reduce credit exposure.

PRINCIPAL RISKS

Please remember that with any mutual fund investment you may lose money.
Principal risks associated with an investment in the Fund include:

ACTIVE MANAGEMENT RISK. The Fund is actively managed and its performance
therefore will reflect in part the ability of the portfolio managers to select
securities and to make investment decisions that are suited to achieving the
Fund's investment objectives. Due to its active management, the Fund could
underperform other mutual funds with similar investment objectives.

CREDIT RISK. Credit risk is the risk that the issuer of a security, or the
counterparty to a contract, will default or otherwise become unable or unwilling
to honor a financial obligation, such as payments due on a bond or a note. If
the Fund purchases unrated securities, or if the rating of a security is reduced
after purchase, the Fund will depend on the investment manager's analysis of
credit risk more heavily than usual.

DERIVATIVES RISK. Derivatives are financial instruments that have a value which
depends upon, or is derived from, the value of something else, such as one or
more underlying securities, pools of securities, options, futures, indexes or
currencies. Gains or losses involving derivative instruments may be substantial,
because a relatively small price movement in the underlying security(ies),
instrument, currency or index may result in a substantial gain or loss for the
Fund. Derivative instruments in which the Fund invests will typically increase
the Fund's exposure to Principal Risks to which it is otherwise exposed, and may
expose the Fund to additional risks, including counterparty credit risk,
leverage risk, hedging risk, correlation risk, and liquidity risk. Counterparty
credit risk is the risk that a counterparty to the derivative instrument becomes
bankrupt or otherwise fails to perform its obligations due to financial
difficulties, and the Fund may obtain no recovery of its investment or may only
obtain a limited recovery, and any recovery may be delayed. Hedging risk is the
risk that derivative instruments used to hedge against an opposite position may
offset losses, but they may also offset gains. Correlation risk is related to
hedging risk and is the risk that there may be an incomplete correlation between
the hedge and the opposite position, which may

- --------------------------------------------------------------------------------
4P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


result in increased or unanticipated losses. Liquidity risk is the risk that the
derivative instrument may be difficult or impossible to sell or terminate, which
may cause the Fund to be in a position to do something the investment manager
would not otherwise choose, including accepting a lower price for the derivative
instrument, selling other investments or foregoing another, more appealing
investment opportunity. Leverage risk is the risk that losses from the
derivative instrument may be greater than the amount invested in the derivative
instrument. Certain derivatives have the potential for unlimited losses,
regardless of the size of the initial investment. See the SAI for more
information on derivative instruments and related risks.

INTEREST RATE RISK. Interest rate risk is the risk of losses attributable to
changes in interest rates. Interest rate risk is generally associated with bond
prices: when interest rates rise, bond prices fall. In general, the longer the
maturity or duration of a bond, the greater its sensitivity to changes in
interest rates.

MARKET RISK. The market value of securities may fall or fail to rise. Market
risk may affect a single issuer, sector of the economy, industry, or the market
as a whole. The market value of securities may fluctuate, sometimes rapidly and
unpredictably.

PREPAYMENT AND EXTENSION RISK. Prepayment and extension risk is the risk that a
bond or other security might be called or otherwise converted, prepaid, or
redeemed before maturity. This risk is primarily associated with asset-backed
securities, including mortgage-backed securities. If a security is converted,
prepaid, or redeemed before maturity, particularly during a time of declining
interest rates, the investment managers may not be able to reinvest in
securities providing as high a level of income, resulting in a reduced yield to
the Fund. Conversely, as interest rates rise, the likelihood of prepayment
decreases. The investment managers may be unable to capitalize on securities
with higher interest rates because the Fund's investments are locked in at a
lower rate for a longer period of time.

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

           RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 5P


PAST PERFORMANCE

The following bar chart and table provide some illustration of the risks of
investing in the Fund by showing, respectively:

- - how the Fund's performance has varied for each full calendar year shown on the
  bar chart; and

- - how the Fund's average annual total returns compare to recognized indexes
  shown on the table.

Both the bar chart and the table assume that all distributions have been
reinvested. The performance of different classes varies because of differences
in sales charges and other fees and expenses. How the Fund has performed in the
past (before and after taxes) does not indicate how the Fund will perform in the
future. Performance reflects any fee waivers/expense caps in effect for the
periods reported. In the absence of such fee waivers/expense caps, performance
would have been lower. See "Fees and Expenses" for any current fee
waivers/expense caps.

Bar Chart. Class A share information is shown in the bar chart; the sales charge
for Class A shares is not reflected in the bar chart.

Table. The table shows total returns from hypothetical investments in Class A,
Class B, Class C, Class I, Class R4 and Class W shares of the Fund. These
returns are compared to the indexes shown for the same periods. For purposes of
the performance calculation in the table we assumed:

- - the maximum sales charge for Class A shares;

- - sales at the end of the period and deduction of the applicable contingent
  deferred sales charge (CDSC) for Class B and Class C shares;

- - no sales charge for Class I, Class R4 and Class W shares; and

- - with the exception of Class A shares, no adjustments for taxes paid by an
  investor on the reinvested income and capital gains.

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

6P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


AFTER-TAX RETURNS

After-tax returns are shown only for Class A shares. After-tax returns for the
other classes will vary. After-tax returns are calculated using the highest
historical individual federal marginal income tax rate and do not reflect the
impact of state and local taxes. Actual after-tax returns will depend on your
tax situation and most likely will differ from the returns shown in the table.
If you hold your shares in a tax-deferred account, such as a 401(k) plan or an
IRA, the after-tax returns do not apply to you since you will not incur taxes
until you begin to withdraw from your account.

The return after taxes on distributions for a period may be the same as the
return before taxes for the same period if there were no distributions or if the
distributions were small. The return after taxes on distributions and sale of
Fund shares for a period may be greater than the return before taxes for the
same period if there was a tax loss realized on sale of Fund shares. The benefit
of the tax loss (since it can be used to offset other gains) may result in a
higher return.

- --------------------------------------------------------------------------------
                           CLASS A SHARE PERFORMANCE
                           (BASED ON CALENDAR YEARS)

                                  (BAR CHART)

<Table>
                                                                                      
              +6.93%     +1.13%     +5.90%     +6.77%     +5.94%     +1.03%     +0.82%     +1.33%     +3.95%     +5.28%
               1998       1999       2000       2001       2002       2003       2004       2005       2006       2007
</Table>

During the periods shown in the bar chart, the highest return for a calendar
quarter was +3.70% (quarter ended Sept. 30, 1998) and the lowest return for a
calendar quarter was -1.49% (quarter ended March 31, 2000).

The 3.00% sales charge applicable to Class A shares of the Fund, which changed
from 4.75% effective March 3, 2008, is not reflected in the bar chart; if
reflected, returns would be lower than those shown. The performance of other
classes may vary from that shown because of differences in expenses.

The Fund's Class A year-to-date return at June 30, 2008 was +0.43%.

The Fund formerly was a "feeder" fund in a master/feeder arrangement where the
Fund invested all of its assets in a corresponding "master" fund with an
identical investment objective and investment strategies. As of Oct. 18, 2005,
the Fund became a stand-alone fund that invests directly in a portfolio of
securities. The information shown in the table and in the financial highlights
for the Fund includes the activity of the Fund when it was a feeder in a
master/feeder arrangement.

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

           RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 7P


AVERAGE ANNUAL TOTAL RETURNS (FOR PERIODS ENDED DEC. 31, 2007)

<Table>
<Caption>
                                                           SINCE       SINCE       SINCE
                                                         INCEPTION   INCEPTION   INCEPTION
                           1 YEAR   5 YEARS   10 YEARS   (CLASS C)   (CLASS I)   (CLASS W)
                                                               
 RiverSource Short
 Duration
 U.S. Government Fund:
   Class A*
      Return before taxes  +0.20%   +1.46%     +3.36%       N/A         N/A         N/A
      Return after taxes
      on distributions     -1.23%   +0.37%     +1.68%       N/A         N/A         N/A
      Return after taxes
      on distributions
      and sale of fund
      shares               +0.11%   +0.60%     +1.81%       N/A         N/A         N/A
   Class B
      Return before taxes  -0.52%   +1.34%     +3.12%       N/A         N/A         N/A
   Class C
      Return before taxes  +3.49%   +1.70%       N/A      +3.32%(a)     N/A         N/A
   Class I
      Return before taxes  +5.89%     N/A        N/A        N/A       +3.16%(b)     N/A
   Class R4
      Return before taxes  +5.43%   +2.64%     +4.05%       N/A         N/A         N/A
   Class W
      Return before taxes  +5.21%     N/A        N/A        N/A         N/A       +4.74%(c)
 Lehman Brothers 1-3 Year
 Government Index
 (reflects no deduction
 for fees, expenses
 or taxes)                 +7.10%   +3.18%     +4.84%     +4.72%(d)   +3.43%(e)   +6.58%(f)
 Lipper Short U.S.
 Government Funds Index    +5.56%   +2.72%     +4.28%     +4.11%(d)   +3.02%(e)   +5.15%(f)
</Table>

 *   On March 3, 2008, the maximum sales charge for Class A shares changed from
     4.75% to 3.00%. Class A share total returns reflect the maximum sales
     charge of 4.75%, which was in effect at the beginning of all periods.
(a)  Inception date is June 26, 2000.
(b)  Inception date is March 4, 2004.
(c)  Inception date is Dec. 1, 2006.
(d)  Measurement period started July 1, 2000.
(e)  Measurement period started March 1, 2004.
(f)  Measurement period started Dec. 1, 2006.

The Lehman Brothers 1-3 Year Government Index, an unmanaged index, is made up of
all publicly issued, non-convertible domestic debt of the U.S. government, or
agency thereof, or any quasi-federal corporation. The index also includes
corporate debt guaranteed by the U.S. government. Only notes and bonds with a
minimum maturity of one year up to a maximum maturity of 2.9 years are included.
The index reflects reinvestment of all distributions and changes in market
prices.

The Lipper Short U.S. Government Funds Index includes the 30 largest short U.S.
government funds tracked by Lipper Inc. The index's returns include net
reinvested dividends.

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

8P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


Past performance for Class W for the period prior to the beginning of operations
may be calculated based on the performance of Class A. The blended class
performance will be adjusted to reflect differences in sales charges, but not
differences in annual Fund operating expenses (for example, 12b-1 fees). The use
of blended performance generally results in a presentation of higher performance
for classes with higher operating expenses than those of the class with which
they are blended, and a presentation of lower performance for classes with lower
operating expenses than those of the class with which they are blended.

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

           RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 9P


FEES AND EXPENSES

Fund investors pay various expenses. The table below describes the fees and
expenses that you may pay if you buy and hold shares of the Fund. Expenses are
based on the Fund's most recent fiscal year.

SHAREHOLDER FEES (FEES PAID DIRECTLY FROM YOUR INVESTMENT)

<Table>
<Caption>

                                                                                    CLASS I
                                                                                    CLASS R4
                                                   CLASS A    CLASS B    CLASS C    CLASS W
                                                                        
 Maximum sales charge (load) imposed on
 purchases
 (as a percentage of offering price)                3.00%(a)   None       None        None
 Maximum deferred sales charge (load) imposed
 on sales
 (as a percentage of offering price at time of
 purchase)                                           None        5%         1%        None
</Table>

ANNUAL FUND OPERATING EXPENSES (EXPENSES THAT ARE DEDUCTED FROM FUND ASSETS)

<Table>
<Caption>

AS A PERCENTAGE OF AVERAGE DAILY NET ASSETS:
                                                   CLASS A    CLASS B    CLASS C    CLASS W
                                                                        
 Management fees                                    0.48%      0.48%      0.48%      0.48%
 Distribution and/or service (12b-1) fees           0.25%      1.00%      1.00%      0.25%
 Other expenses(b)                                  0.31%      0.32%      0.32%      0.33%
 Total annual fund operating expenses               1.04%      1.80%      1.80%      1.06%
 Fee waiver/expense reimbursement                   0.15%      0.15%      0.15%      0.10%
 Total annual (net) fund operating expenses(c)      0.89%      1.65%      1.65%      0.96%
</Table>

<Table>
<Caption>

                                                                CLASS I    CLASS R4
                                                                     
 Management fees                                                 0.48%      0.48%
 Distribution and/or service (12b-1) fees                        0.00%      0.00%
 Other expenses(b)                                               0.12%      0.42%
 Total annual fund operating expenses                            0.60%      0.90%
 Fee waiver/expense reimbursement                                0.09%      0.14%
 Total annual (net) fund operating expenses(c)                   0.51%      0.76%
</Table>

(a)  This charge may be reduced depending on the value of your total investments
     in RiverSource Funds. See "Sales Charges."
(b)  Other expenses include an administrative services fee, a transfer agency
     fee, (for all classes except Class I), a custody fee, other nonadvisory
     expenses and a plan administration services fee (for Class R4). Other
     expenses may also include fees and expenses of affiliated and unaffiliated
     funds (acquired funds) which the Fund indirectly bears when it invests in
     the acquired funds. The impact of these acquired funds fees and expenses
     for the most recent fiscal period was less than 0.01%. Because acquired
     funds will have varied expense and fee levels and the Fund may own
     different proportions of acquired funds at different times, the amount of
     fees and expenses incurred by the Fund with respect to such investments
     will vary.
(c)  The investment manager and its affiliates have contractually agreed to
     waive certain fees and to absorb certain expenses until May 31, 2009,
     unless sooner terminated at the discretion of the Fund's Board. Any amounts
     waived will not be reimbursed by the Fund. Under this agreement, net fund
     expenses (excluding fees and expenses of acquired funds), will not exceed
     0.89% for Class A, 1.65% for Class B, 1.65% for Class C, 0.51% for Class I,
     0.76% for Class R4 and 0.96% for Class W.

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

10P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


EXAMPLES

These examples are intended to help you compare the cost of investing in the
Fund with the cost of investing in other mutual funds.

These examples assume that you invest $10,000 in the Fund for the time periods
indicated and then redeem all of your shares at the end of those periods. These
examples also assume that your investment has a 5% return each year and that the
Fund's operating expenses remain the same. Although your actual costs may be
higher or lower, based on these assumptions your costs would be:

<Table>
<Caption>
                                             1 YEAR      3 YEARS      5 YEARS      10 YEARS
                                                                       
 Class A(a)                                   $388        $607        $  844        $1,524
 Class B                                      $668(b)     $952(b)     $1,162(b)     $1,908(c)
 Class C                                      $268(b)     $552        $  962        $2,109
 Class I                                      $ 52        $183        $  327        $  745
 Class R4                                     $ 78        $273        $  486        $1,099
 Class W                                      $ 98        $328        $  576        $1,290
</Table>

(a)  Includes a 3.00% sales charge.
(b)  Includes the applicable CDSC.
(c)  Based on conversion of Class B shares to Class A shares in the ninth year
     of ownership.

You would pay the following expenses if you did not redeem your shares:

<Table>
<Caption>
                                             1 YEAR      3 YEARS      5 YEARS      10 YEARS
                                                                       
 Class A(a)                                   $388        $607        $  844        $1,524
 Class B                                      $168        $552        $  962        $1,908(b)
 Class C                                      $168        $552        $  962        $2,109
 Class I                                      $ 52        $183        $  327        $  745
 Class R4                                     $ 78        $273        $  486        $1,099
 Class W                                      $ 98        $328        $  576        $1,290
</Table>

(a)  Includes a 3.00% sales charge.
(b)  Based on conversion of Class B shares to Class A shares in the ninth year
     of ownership.

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

          RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 11P


OTHER INVESTMENT STRATEGIES AND RISKS

Other Investment Strategies. In addition to the principal investment strategies
previously described, the Fund may utilize investment strategies that are not
principal investment strategies, including investment in affiliated and
non-affiliated pooled investment vehicles (including mutual funds and exchange
traded funds (ETFs), also referred to as "acquired funds") ownership of which
results in the Fund bearing its proportionate share of the acquired funds' fees
and expenses. Although ETFs are designed to replicate the price and yield of a
specified market index, there is no guarantee that an ETF will track its
specified market index, which may result in a loss. For more information on
strategies and holdings, and the risks of such strategies, including derivative
instruments that the Fund may use, see the Fund's SAI and its annual and
semiannual reports.

Unusual Market Conditions. During unusual market conditions, the Fund may
temporarily invest more of its assets in money market securities than during
normal market conditions. Although investing in these securities would serve
primarily to attempt to avoid losses, this type of investing also could prevent
the Fund from achieving its investment objective. During these times, the
portfolio managers may make frequent securities trades that could result in
increased fees, expenses and taxes, and decreased performance. Instead of
investing in money market securities directly, the Fund may invest in shares of
an affiliated money market fund. See "Cash Reserves" for more information.

Securities Transaction Commissions. Securities transactions involve the payment
by the Fund of brokerage commissions to broker-dealers, on occasion as
compensation for research or brokerage services (commonly referred to as "soft
dollars"), as the portfolio managers buy and sell securities for the Fund in
pursuit of its objective. A description of the policies governing the Fund's
securities transactions and the dollar value of brokerage commissions paid by
the Fund are set forth in the SAI. Funds that invest primarily in fixed income
securities do not typically generate brokerage commissions that are used to pay
for research or brokerage services. The brokerage commissions set forth in the
SAI do not include implied commissions or mark-ups (implied commissions) paid by
the Fund for principal transactions (transactions made directly with a dealer or
other counterparty), including most fixed income securities (and certain other
instruments, including derivatives). Brokerage commissions do not reflect other
elements of transaction costs, including the extent to which the Fund's purchase
and sale transactions may cause the market to move and change the market price
for an investment.

Although brokerage commissions and implied commissions are not reflected in the
expense table under "Fees and Expenses," they are reflected in the total return
of the Fund.

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

12P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


Portfolio Turnover. Trading of securities may produce capital gains, which are
taxable to shareholders when distributed. Active trading may also increase the
amount of brokerage commissions paid or mark-ups to broker-dealers that the Fund
pays when it buys and sells securities. Capital gains and increased brokerage
commissions or mark-ups paid to broker-dealers may adversely affect a fund's
performance. The Fund's historical portfolio turnover rate, which measures how
frequently the Fund buys and sells investments, is shown in the "Financial
Highlights."

Directed Brokerage. The Fund's Board of Directors (Board) has adopted a policy
prohibiting the investment manager, or any subadviser, from considering sales of
shares of the Fund as a factor in the selection of broker-dealers through which
to execute securities transactions.

Additional information regarding securities transactions can be found in the
SAI.

FUND MANAGEMENT AND COMPENSATION

INVESTMENT MANAGER

RiverSource Investments, LLC (the investment manager or RiverSource
Investments), 200 Ameriprise Financial Center, Minneapolis, Minnesota 55474, is
the investment manager to the RiverSource funds, and is a wholly-owned
subsidiary of Ameriprise Financial, Inc. (Ameriprise Financial). Ameriprise
Financial is a financial planning and financial services company that has been
offering solutions for clients' asset accumulation, income management and
protection needs for more than 110 years. In addition to managing investments
for all of the RiverSource funds, RiverSource Investments manages investments
for itself and its affiliates. For institutional clients, RiverSource
Investments and its affiliates provide investment management and related
services, such as separate account asset management, and institutional trust and
custody, as well as other investment products. For all of its clients,
RiverSource Investments seeks to allocate investment opportunities in an
equitable manner over time. See the SAI for more information.

The Fund pays RiverSource Investments a fee for managing its assets. Under the
Investment Management Services Agreement (Agreement), the fee for the most
recent fiscal year was 0.48% of the Fund's average daily net assets. Under the
Agreement, the Fund also pays taxes, brokerage commissions, and nonadvisory
expenses. A discussion regarding the basis for the Board approving the Agreement
is available in the Fund's most recent annual or semiannual shareholder report.

Portfolio Manager(s). The portfolio managers responsible for the day-to-day
management of the Fund are:

Scott Kirby, Portfolio Manager

- - Began managing the Fund in 2001.
- - Leader of the structured assets sector team.

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

          RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 13P


- - Employed by RiverSource Investments from 1979 to 1985 and from 1987 to
  present.

- - Began investment career in 1979.

- - MBA, University of Minnesota.

Jamie Jackson, CFA, Portfolio Manager

- - Began managing the Fund in 2003.

- - Leader of the liquid assets sector team.

- - Joined RiverSource Investments in 2003.

- - Co-head of U.S. Investment Grade Fixed Income, UBS Global Asset Management,
  1997 to 2003.

- - Began investment career in 1988.

- - MBA, Marquette University.

The fixed income department of RiverSource Investments is divided into six
sector teams, each of which includes a portfolio manager or portfolio managers
and several analysts, and each of which specializes in a specific sector of the
fixed income market. The Fund's portfolio managers lead the teams that
specialize in the sectors in which the Fund primarily invests, and collectively
determine allocation of Fund assets among the sectors.

The SAI provides additional information about portfolio manager compensation,
management of other accounts and ownership of shares in the Fund.

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

14P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


FINANCIAL HIGHLIGHTS

THE FINANCIAL HIGHLIGHTS TABLES ARE INTENDED TO HELP YOU UNDERSTAND THE FUND'S
FINANCIAL PERFORMANCE. CERTAIN INFORMATION REFLECTS FINANCIAL RESULTS FOR A
SINGLE FUND SHARE. THE TOTAL RETURNS IN THE TABLES REPRESENT THE RATE THAT AN
INVESTOR WOULD HAVE EARNED OR LOST ON AN INVESTMENT IN THE FUND (ASSUMING
REINVESTMENT OF ALL DIVIDENDS AND DISTRIBUTIONS). THE INFORMATION FOR THE FISCAL
YEAR ENDED MAY 31, 2008 HAS BEEN DERIVED FROM THE FINANCIAL STATEMENTS AUDITED
BY ERNST & YOUNG LLP, WHOSE REPORT, ALONG WITH THE FUND'S FINANCIAL STATEMENTS
AND FINANCIAL HIGHLIGHTS, IS INCLUDED IN THE ANNUAL REPORT WHICH, IF NOT
INCLUDED WITH THIS PROSPECTUS, IS AVAILABLE UPON REQUEST. THE INFORMATION FOR
THE PERIODS ENDED ON OR BEFORE MAY 31, 2007 HAS BEEN AUDITED BY KPMG LLP.

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

          RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 15P


CLASS A

<Table>
<Caption>
PER SHARE INCOME AND CAPITAL CHANGES(a)
FISCAL PERIOD ENDED MAY 31,             2008              2007           2006           2005           2004
                                                                                   
Net asset value, beginning of period      $4.73          $4.68          $4.79          $4.82          $4.94
- -----------------------------------------------------------------------------------------------------------
INCOME FROM INVESTMENT OPERATIONS:
Net investment income (loss)                .19(b)         .19            .15            .12            .11
Net gains (losses) (both realized and
 unrealized)                                .01            .05           (.10)          (.03)          (.12)
- -----------------------------------------------------------------------------------------------------------
Total from investment operations            .20            .24            .05            .09           (.01)
- -----------------------------------------------------------------------------------------------------------
LESS DISTRIBUTIONS:
Dividends from net investment income       (.19)          (.19)          (.16)          (.12)          (.11)
- -----------------------------------------------------------------------------------------------------------
Net asset value, end of period            $4.74          $4.73          $4.68          $4.79          $4.82
- -----------------------------------------------------------------------------------------------------------
RATIOS TO AVERAGE NET ASSETS/SUPPLEMENTAL DATA
Net assets, end of period (in
 millions)                                 $539           $514           $641           $894         $1,188
- -----------------------------------------------------------------------------------------------------------
Gross expenses prior to expense
 waiver/reimbursement(c),(d)              1.04%          1.03%          1.06%          1.01%           .97%
- -----------------------------------------------------------------------------------------------------------
Net expenses after expense
 waiver/reimbursement(d),(e),(f)           .89%           .89%           .89%           .93%           .97%
- -----------------------------------------------------------------------------------------------------------
Net investment income (loss)              3.93%          3.99%          3.27%          2.49%          2.19%
- -----------------------------------------------------------------------------------------------------------
Portfolio turnover rate                    209%           168%           194%           169%           125%
- -----------------------------------------------------------------------------------------------------------
Total return(g)                           4.27%          5.12%          1.00%          1.92%          (.24%)
- -----------------------------------------------------------------------------------------------------------
</Table>

(a)  For a share outstanding throughout the period. Rounded to the nearest cent.
(b)  Per share amount has been calculated using the average shares outstanding
     method.
(c)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances.
(d)  In addition to the fees and expenses which the Fund bears directly, the
     Fund indirectly bears a pro rata share of the fees and expenses of the
     acquired funds in which it invests. Such indirect expenses are not included
     in the above reported expense ratios.
(e)  The Investment Manager and its affiliates have agreed to waive/reimburse
     certain fees and expenses (excluding fees and expenses of acquired funds).
(f)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances. The ratio of net expenses after expense waiver/reimbursement and
     after reduction for earnings and bank fee credits was 0.88% for the year
     ended May 31, 2008.
(g)  Total return does not reflect payment of a sales charge.

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

16P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


CLASS B

<Table>
<Caption>
PER SHARE INCOME AND CAPITAL CHANGES(a)
FISCAL PERIOD ENDED MAY 31,             2008              2007           2006           2005           2004
                                                                                   
Net asset value, beginning of period      $4.73          $4.68          $4.79          $4.82          $4.94
- -----------------------------------------------------------------------------------------------------------
INCOME FROM INVESTMENT OPERATIONS:
Net investment income (loss)                .15(b)         .15            .12            .08            .07
Net gains (losses) (both realized and
 unrealized)                                .01            .05           (.11)          (.03)          (.12)
- -----------------------------------------------------------------------------------------------------------
Total from investment operations            .16            .20            .01            .05           (.05)
- -----------------------------------------------------------------------------------------------------------
LESS DISTRIBUTIONS:
Dividends from net investment income       (.15)          (.15)          (.12)          (.08)          (.07)
- -----------------------------------------------------------------------------------------------------------
Net asset value, end of period            $4.74          $4.73          $4.68          $4.79          $4.82
- -----------------------------------------------------------------------------------------------------------
RATIOS TO AVERAGE NET ASSETS/SUPPLEMENTAL DATA
Net assets, end of period (in
 millions)                                 $159           $216           $338           $588           $963
- -----------------------------------------------------------------------------------------------------------
Gross expenses prior to expense
 waiver/reimbursement(c),(d)              1.80%          1.79%          1.82%          1.76%          1.72%
- -----------------------------------------------------------------------------------------------------------
Net expenses after expense
 waiver/reimbursement(d),(e),(f)          1.65%          1.64%          1.64%          1.68%          1.72%
- -----------------------------------------------------------------------------------------------------------
Net investment income (loss)              3.18%          3.23%          2.50%          1.73%          1.44%
- -----------------------------------------------------------------------------------------------------------
Portfolio turnover rate                    209%           168%           194%           169%           125%
- -----------------------------------------------------------------------------------------------------------
Total return(g)                           3.48%          4.34%           .26%          1.16%          (.99%)
- -----------------------------------------------------------------------------------------------------------
</Table>

(a)  For a share outstanding throughout the period. Rounded to the nearest cent.
(b)  Per share amount has been calculated using the average shares outstanding
     method.
(c)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances.
(d)  In addition to the fees and expenses which the Fund bears directly, the
     Fund indirectly bears a pro rata share of the fees and expenses of the
     acquired funds in which it invests. Such indirect expenses are not included
     in the above reported expense ratios.
(e)  The Investment Manager and its affiliates have agreed to waive/reimburse
     certain fees and expenses (excluding fees and expenses of acquired funds).
(f)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances. The ratio of net expenses after expense waiver/reimbursement and
     after reduction for earnings and bank fee credits was 1.64% for the year
     ended May 31, 2008.
(g)  Total return does not reflect payment of a sales charge.

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

          RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 17P


CLASS C

<Table>
<Caption>
PER SHARE INCOME AND CAPITAL CHANGES(a)
FISCAL PERIOD ENDED MAY 31,             2008              2007           2006           2005           2004
                                                                                   
Net asset value, beginning of period      $4.73          $4.68          $4.79          $4.82          $4.94
- -----------------------------------------------------------------------------------------------------------
INCOME FROM INVESTMENT OPERATIONS:
Net investment income (loss)                .15(b)         .15            .12            .08            .07
Net gains (losses) (both realized and
 unrealized)                                .02            .05           (.11)          (.03)          (.12)
- -----------------------------------------------------------------------------------------------------------
Total from investment operations            .17            .20            .01            .05           (.05)
- -----------------------------------------------------------------------------------------------------------
LESS DISTRIBUTIONS:
Dividends from net investment income       (.16)          (.15)          (.12)          (.08)          (.07)
- -----------------------------------------------------------------------------------------------------------
Net asset value, end of period            $4.74          $4.73          $4.68          $4.79          $4.82
- -----------------------------------------------------------------------------------------------------------
RATIOS TO AVERAGE NET ASSETS/SUPPLEMENTAL DATA
Net assets, end of period (in
 millions)                                  $10            $10            $15            $24            $38
- -----------------------------------------------------------------------------------------------------------
Gross expenses prior to expense
 waiver/reimbursement(c),(d)              1.80%          1.80%          1.83%          1.77%          1.73%
- -----------------------------------------------------------------------------------------------------------
Net expenses after expense
 waiver/reimbursement(d),(e),(f)          1.65%          1.64%          1.64%          1.68%          1.73%
- -----------------------------------------------------------------------------------------------------------
Net investment income (loss)              3.18%          3.24%          2.51%          1.73%          1.44%
- -----------------------------------------------------------------------------------------------------------
Portfolio turnover rate                    209%           168%           194%           169%           125%
- -----------------------------------------------------------------------------------------------------------
Total return(g)                           3.49%          4.34%           .26%          1.16%          (.99%)
- -----------------------------------------------------------------------------------------------------------
</Table>

(a)  For a share outstanding throughout the period. Rounded to the nearest cent.
(b)  Per share amount has been calculated using the average shares outstanding
     method.
(c)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances.
(d)  In addition to the fees and expenses which the Fund bears directly, the
     Fund indirectly bears a pro rata share of the fees and expenses of the
     acquired funds in which it invests. Such indirect expenses are not included
     in the above reported expense ratios.
(e)  The Investment Manager and its affiliates have agreed to waive/reimburse
     certain fees and expenses (excluding fees and expenses of acquired funds).
(f)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances. The ratio of net expenses after expense waiver/reimbursement and
     after reduction for earnings and bank fee credits was 1.64% for the year
     ended May 31, 2008.
(g)  Total return does not reflect payment of a sales charge.

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

18P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


CLASS I

<Table>
<Caption>
PER SHARE INCOME AND CAPITAL CHANGES(a)
FISCAL PERIOD ENDED MAY 31,             2008              2007           2006           2005        2004(B)
                                                                                   
Net asset value, beginning of period      $4.74          $4.69          $4.79          $4.83          $4.90
- -----------------------------------------------------------------------------------------------------------
INCOME FROM INVESTMENT OPERATIONS:
Net investment income (loss)                .20(c)         .20            .17            .14            .03
Net gains (losses) (both realized and
 unrealized)                                .01            .05           (.10)          (.04)          (.07)
- -----------------------------------------------------------------------------------------------------------
Total from investment operations            .21            .25            .07            .10           (.04)
- -----------------------------------------------------------------------------------------------------------
LESS DISTRIBUTIONS:
Dividends from net investment income       (.21)          (.20)          (.17)          (.14)          (.03)
- -----------------------------------------------------------------------------------------------------------
Net asset value, end of period            $4.74          $4.74          $4.69          $4.79          $4.83
- -----------------------------------------------------------------------------------------------------------
RATIOS TO AVERAGE NET ASSETS/SUPPLEMENTAL DATA
Net assets, end of period (in
 millions)                                  $93            $55            $62            $31             $4
- -----------------------------------------------------------------------------------------------------------
Gross expenses prior to expense
 waiver/reimbursement(d),(e)               .60%           .59%           .62%           .57%           .63%(f)
- -----------------------------------------------------------------------------------------------------------
Net expenses after expense
 waiver/reimbursement(e),(g),(h)           .51%           .54%           .58%           .57%           .63%(f)
- -----------------------------------------------------------------------------------------------------------
Net investment income (loss)              4.23%          4.37%          3.66%          2.98%          2.74%(f)
- -----------------------------------------------------------------------------------------------------------
Portfolio turnover rate                    209%           168%           194%           169%           125%
- -----------------------------------------------------------------------------------------------------------
Total return                              4.45%          5.50%          1.56%          2.06%          (.87%)(i)
- -----------------------------------------------------------------------------------------------------------
</Table>

(a)  For a share outstanding throughout the period. Rounded to the nearest cent.
(b)  For the period from March 4, 2004 (inception date) to May 31, 2004.
(c)  Per share amount has been calculated using the average shares outstanding
     method.
(d)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances.
(e)  In addition to the fees and expenses which the Fund bears directly, the
     Fund indirectly bears a pro rata share of the fees and expenses of the
     acquired funds in which it invests. Such indirect expenses are not included
     in the above reported expense ratios.
(f)  Adjusted to an annual basis.
(g)  The Investment Manager and its affiliates have agreed to waive/reimburse
     certain fees and expenses (excluding fees and expenses of acquired funds).
(h)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances. The ratio of net expenses after expense waiver/reimbursement and
     after reduction for earnings and bank fee credits was 0.50% for the year
     ended May 31, 2008.
(i)  Not annualized.

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

          RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 19P


CLASS R4

<Table>
<Caption>
PER SHARE INCOME AND CAPITAL CHANGES(a)
FISCAL PERIOD ENDED MAY 31,             2008              2007           2006           2005           2004
                                                                                   
Net asset value, beginning of period      $4.73          $4.68          $4.79          $4.82          $4.94
- -----------------------------------------------------------------------------------------------------------
INCOME FROM INVESTMENT OPERATIONS:
Net investment income (loss)                .19(b)         .19            .16            .13            .12
Net gains (losses) (both realized and
 unrealized)                                .02            .05           (.11)          (.03)          (.12)
- -----------------------------------------------------------------------------------------------------------
Total from investment operations            .21            .24            .05            .10             --
- -----------------------------------------------------------------------------------------------------------
LESS DISTRIBUTIONS:
Dividends from net investment income       (.20)          (.19)          (.16)          (.13)          (.12)
- -----------------------------------------------------------------------------------------------------------
Net asset value, end of period            $4.74          $4.73          $4.68          $4.79          $4.82
- -----------------------------------------------------------------------------------------------------------
RATIOS TO AVERAGE NET ASSETS/SUPPLEMENTAL DATA
Net assets, end of period (in
 millions)                                   $5             $4            $19           $100           $115
- -----------------------------------------------------------------------------------------------------------
Gross expenses prior to expense
 waiver/reimbursement(c),(d)               .90%           .86%           .88%           .84%           .81%
- -----------------------------------------------------------------------------------------------------------
Net expenses after expense
 waiver/reimbursement(d),(e),(f)           .76%           .72%           .72%           .76%           .81%
- -----------------------------------------------------------------------------------------------------------
Net investment income (loss)              4.06%          4.09%          3.27%          2.66%          2.35%
- -----------------------------------------------------------------------------------------------------------
Portfolio turnover rate                    209%           168%           194%           169%           125%
- -----------------------------------------------------------------------------------------------------------
Total return                              4.41%          5.31%          1.19%          2.10%          (.08%)
- -----------------------------------------------------------------------------------------------------------
</Table>

(a)  For a share outstanding throughout the period. Rounded to the nearest cent.
(b)  Per share amount has been calculated using the average shares outstanding
     method.
(c)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances.
(d)  In addition to the fees and expenses which the Fund bears directly, the
     Fund indirectly bears a pro rata share of the fees and expenses of the
     acquired funds in which it invests. Such indirect expenses are not included
     in the above reported expense ratios.
(e)  The Investment Manager and its affiliates have agreed to waive/reimburse
     certain fees and expenses (excluding fees and expenses of acquired funds).
(f)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances. The ratio of net expenses after expense waiver/reimbursement and
     after reduction for earnings and bank fee credits was 0.75% for the year
     ended May 31, 2008.

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

20P RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS


CLASS W

<Table>
<Caption>
PER SHARE INCOME AND CAPITAL CHANGES(a)
FISCAL PERIOD ENDED MAY 31,             2008           2007(B)
                                                                                   
Net asset value, beginning of period      $4.73          $4.75
- -----------------------------------------------------------------------------------------------------------
INCOME FROM INVESTMENT OPERATIONS:
Net investment income (loss)                .18(c)         .08
Net gains (losses) (both realized and
 unrealized)                                .02           (.02)
- -----------------------------------------------------------------------------------------------------------
Total from investment operations            .20            .06
- -----------------------------------------------------------------------------------------------------------
LESS DISTRIBUTIONS:
Dividends from net investment income       (.19)          (.08)
- -----------------------------------------------------------------------------------------------------------
Net asset value, end of period            $4.74          $4.73
- -----------------------------------------------------------------------------------------------------------
RATIOS TO AVERAGE NET ASSETS/SUPPLEMENTAL DATA
Net assets, end of period (in
 millions)                                  $--            $--
- -----------------------------------------------------------------------------------------------------------
Gross expenses prior to expense
 waiver/reimbursement(d),(e)              1.06%          1.00%(f)
- -----------------------------------------------------------------------------------------------------------
Net expenses after expense
 waiver/reimbursement(e),(g),(h)           .95%           .95%(f)
- -----------------------------------------------------------------------------------------------------------
Net investment income (loss)              3.87%          4.02%(f)
- -----------------------------------------------------------------------------------------------------------
Portfolio turnover rate                    209%           168%
- -----------------------------------------------------------------------------------------------------------
Total return                              4.21%          1.42%(i)
- -----------------------------------------------------------------------------------------------------------
</Table>

(a)  For a share outstanding throughout the period. Rounded to the nearest cent.
(b)  For the period from Dec. 1, 2006 (inception date) to May 31, 2007.
(c)  Per share amount has been calculated using the average shares outstanding
     method.
(d)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances.
(e)  In addition to the fees and expenses which the Fund bears directly, the
     Fund indirectly bears a pro rata share of the fees and expenses of the
     acquired funds in which it invests. Such indirect expenses are not included
     in the above reported expense ratios.
(f)  Adjusted to an annual basis.
(g)  The Investment Manager and its affiliates have agreed to waive/reimburse
     certain fees and expenses (excluding fees and expenses of acquired funds).
(h)  Expense ratio is before reduction for earnings and bank fee credits on cash
     balances. Earnings and bank fee credits for the year ended May 31, 2008
     were less than 0.01% of average net assets.
(i)  Not annualized.

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

          RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND -- 2008 PROSPECTUS 21P


RIVERSOURCE COMPLEX OF FUNDS

THE RIVERSOURCE COMPLEX OF FUNDS INCLUDES FUNDS BRANDED "RIVERSOURCE,"
"RIVERSOURCE PARTNERS," AND "THREADNEEDLE" (EACH INDIVIDUALLY, A "FUND" OR A
"RIVERSOURCE FUND" AND COLLECTIVELY, THE "FUNDS" OR THE "RIVERSOURCE FUNDS").
THESE FUNDS SHARE THE SAME BOARD OF DIRECTORS/TRUSTEES (THE "BOARD"), AND THE
SAME POLICIES AND PROCEDURES INCLUDING THOSE SET FORTH IN THIS SERVICE SECTION.
FOR EXAMPLE, FOR PURPOSES OF CALCULATING THE INITIAL SALES CHARGE ON THE
PURCHASE OF CLASS A SHARES OF A FUND, AN INVESTOR OR FINANCIAL ADVISOR SHOULD
CONSIDER THE COMBINED MARKET VALUE OF ALL RIVERSOURCE FUNDS (INCLUDING
"THREADNEEDLE" OR "RIVERSOURCE PARTNERS" BRANDED FUNDS), OWNED BY THE INVESTOR
AS DEFINED UNDER "INITIAL SALES CHARGE -- RIGHTS OF ACCUMULATION (ROA)."

BUYING AND SELLING SHARES

The RiverSource funds are generally available directly and through
broker-dealers, banks and other financial intermediaries or institutions
(financial institutions), including certain qualified and non-qualified plans,
wrap fee products or other investment products sponsored by financial
institutions. THESE FINANCIAL INSTITUTIONS MAY CHARGE YOU ADDITIONAL FEES FOR
THE SERVICES THEY PROVIDE AND THEY MAY HAVE DIFFERENT POLICIES NOT DESCRIBED IN
THIS PROSPECTUS. Some policy differences may include different minimum
investment amounts, exchange privileges, fund choices and cutoff times for
investments. Additionally, recordkeeping, transaction processing and payments of
distributions relating to your account may be performed by the financial
institutions through which your shares of the fund(s) are held. Since the fund
(and its service providers) may not have a record of your account transactions,
you should always contact the financial institution through which you purchased
or at which you maintain your shares of the fund to make changes to your account
or to give instructions concerning your account, or to obtain information about
your account. The fund and its service providers, including the distributor and
the transfer agent, are not responsible for the failure of one of these
financial institutions to carry out its obligations to its customers.

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

S.1                                                                     S-6400-6


DESCRIPTION OF SHARE CLASSES

INVESTMENT OPTIONS -- CLASSES OF SHARES

The RiverSource funds offer different classes of shares. There are differences
among the fees and expenses for each share class. See the "Fees and Expenses"
table for more information. Not everyone is eligible to buy every share class.
After determining which share classes you are eligible to buy, decide which
share class best suits your needs. Your financial institution can help you with
this decision. The following table shows the key features of each share class.
(THE COVER OF THIS PROSPECTUS INDICATES WHICH SHARE CLASSES ARE CURRENTLY
OFFERED FOR THIS FUND.)

INVESTMENT OPTIONS SUMMARY

<Table>
<Caption>
                                                  CONTINGENT                                   PLAN
                               INITIAL            DEFERRED SALES             DISTRIBUTION AND  ADMINISTRATION
           AVAILABILITY(A)     SALES CHARGE       CHARGE (CDSC)              SERVICE FEE(B)    FEE
- -------------------------------------------------------------------------------------------------------------
                                                                                
Class A    Available to        Yes. Payable at    No.                        Yes.              No.
           all investors.      time of purchase.                             0.25%
                               Lower or no sales
                               charge for larger
                               investments.
- -------------------------------------------------------------------------------------------------------------
Class      Available to        No. Entire         Maximum 5% CDSC during     Yes.              No.
  B(c)(d)  all investors.      purchase price is  the first year decreasing  1.00%
                               invested in        to 0% after six years.
                               shares of the
                               fund.
- -------------------------------------------------------------------------------------------------------------
Class C    Available to        No. Entire         1% CDSC may apply if you   Yes.              No.
           all investors.      purchase price is  sell shares within one     1.00%
                               invested in        year after purchase.
                               shares of the
                               fund.
- -------------------------------------------------------------------------------------------------------------
Class I    Limited to          No.                No.                        No.               No.
           qualifying
           institutional
           investors.
- -------------------------------------------------------------------------------------------------------------
Class R2   Limited to          No.                No.                        Yes.              Yes.
           qualifying                                                        0.50%             0.25%
           institutional
           investors.
- -------------------------------------------------------------------------------------------------------------
Class R3   Limited to          No.                No.                        Yes.              Yes.
           qualifying                                                        0.25%             0.25%
           institutional
           investors.
- -------------------------------------------------------------------------------------------------------------
Class R4   Limited to          No.                No.                        No.               Yes.
           qualifying                                                                          0.25%
           institutional
           investors.
- -------------------------------------------------------------------------------------------------------------
Class R5   Limited to          No.                No.                        No.               No.
           qualifying
           institutional
           investors.
- -------------------------------------------------------------------------------------------------------------
</Table>

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

                                                                             S.2


<Table>
<Caption>
INVESTMENT OPTIONS SUMMARY (CONTINUED)
                                                  CONTINGENT                                   PLAN
                               INITIAL            DEFERRED SALES             DISTRIBUTION AND  ADMINISTRATION
           AVAILABILITY(A)     SALES CHARGE       CHARGE (CDSC)              SERVICE FEE(B)    FEE
- -------------------------------------------------------------------------------------------------------------
                                                                                
Class W    Limited to          No.                No.                        Yes.              No.
           qualifying                                                        0.25%
           discretionary
           managed accounts.
- -------------------------------------------------------------------------------------------------------------
</Table>

(a)  See "Buying and Selling Shares, Determining which class of shares to
     purchase" for more information on availability of share classes and
     eligible investors. See "Buying and Selling Shares, Opening an Account" for
     information on minimum investment and account balance requirements.
(b)  For each of Class A, Class B, Class C, Class R2, Class R3 and Class W
     shares, as applicable, each fund has adopted a plan under Rule 12b-1 of the
     Investment Company Act of 1940, as amended, that allows it to pay
     distribution and shareholder servicing-related expenses for the sale of
     shares and the servicing of shareholders. This plan has been reviewed and
     approved by the Board. Because these fees are paid out of fund assets on an
     on-going basis, over time these fees will increase the cost of your
     investment and may cost you more than paying other types of distribution
     (sales) or servicing charges.
(c)  See "Buying and Selling Shares, Sales Charges, Class B and Class
     C -- contingent deferred sales charge alternative" for more information on
     the timing of conversion of Class B shares to Class A shares. Timing of
     conversion will vary depending on the date of your original purchase of the
     Class B shares.
(d)  Class B shares of each of RiverSource Floating Rate Fund, RiverSource
     Inflation Protected Securities Fund, RiverSource Intermediate Tax-Exempt
     Fund, RiverSource Limited Duration Bond Fund and RiverSource Short Duration
     U.S. Government Fund are closed to new investors and new purchases.
     (Existing shareholders in these funds may continue to own Class B shares
     and make exchanges into and out of existing accounts where Class B shares
     of these funds are maintained.)

DISTRIBUTION AND SERVICE FEES

The distribution and shareholder servicing fees for Class A, Class B, Class C,
Class R2, Class R3 and Class W shares are subject to the requirements of Rule
12b-1 under the Investment Company Act of 1940, as amended, and are used to
reimburse the distributor for certain expenses it incurs in connection with
distributing a fund's shares and directly or indirectly providing services to
fund shareholders. These expenses include payment of distribution and
shareholder servicing fees to financial institutions that sell shares of the
fund or provide services to fund shareholders, up to 0.50% of the average daily
net assets of Class R2 shares sold and held through them and up to 0.25% of the
average daily net assets of Class A, Class B, Class C, Class R3 and Class W
shares sold and held through them. For Class A, Class B, Class R2, Class R3 and
Class W shares, the distributor begins to pay these fees immediately after
purchase. For Class C shares, the distributor pays these fees in advance for the
first 12 months. Financial institutions also receive distribution fees up to
0.75% of the average daily net assets of Class C shares sold and held through
them, which the distributor begins to pay 12 months after purchase. For Class B
shares, and, for the first 12 months following the sale of Class C shares, the
fund's distributor retains the distribution fee of up to 0.75% in order to
finance the payment of sales commissions to financial institutions that sell
Class B shares, and to pay for other distribution related expenses. Financial
institutions may compensate their financial advisors

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

S.3


with the shareholder servicing and distribution fees paid to them by the
distributor. IF YOU MAINTAIN SHARES OF THE FUND DIRECTLY WITH THE FUND, WITHOUT
WORKING DIRECTLY WITH A FINANCIAL INSTITUTION OR FINANCIAL ADVISOR, DISTRIBUTION
AND SERVICE FEES WILL BE RETAINED BY THE DISTRIBUTOR.

PLAN ADMINISTRATION FEE

Class R2, Class R3 and Class R4 shares pay an annual plan administration
services fee for the provision of various administrative, recordkeeping,
communication and educational services. The fee for Class R2, Class R3 and Class
R4 shares is equal on an annual basis to 0.25% of average daily net assets
attributable to the respective class.

DETERMINING WHICH CLASS OF SHARES TO PURCHASE

CLASS A, CLASS B AND CLASS C SHARES.

New purchases of Class B shares will not be permitted if your Rights of
Accumulation are $50,000 or higher, and new purchases of Class C shares will not
be permitted if your Rights of Accumulation are $1,000,000 or higher. See "Sales
Charges, Initial Sales Charge -- Rights of Accumulation (ROA)" for information
on Rights of Accumulation.

Class B shares have a higher annual distribution fee than Class A shares and a
contingent deferred sales charge (CDSC) for six years. Class B shares convert to
Class A shares in the ninth year of ownership. Class B shares purchased through
reinvested dividends and distributions also will convert to Class A shares in
the same proportion as the other Class B shares.

Class C shares also have a higher annual distribution fee than Class A shares.
Class C shares have no sales charge if you hold the shares for longer than one
year. Unlike Class B shares, Class C shares do not convert to Class A shares. As
a result, you will pay a distribution fee for as long as you hold Class C
shares. If you choose a deferred sales charge option (Class B or Class C), you
should consider the length of time you intend to hold your shares. To help you
determine which investment is best for you, consult your financial institution.

CLASS I SHARES.

The following eligible investors may purchase Class I shares:

- - Any fund distributed by RiverSource Distributors, Inc., if the fund seeks to
  achieve its investment objective by investing primarily in shares of the fund
  and other RiverSource funds.

Class I shares may be purchased, sold or exchanged only through the distributor
or an authorized financial institution.

CLASS R SHARES.

The following eligible institutional investors may purchase Class R2, Class R3,
Class R4 and Class R5 shares:

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

                                                                             S.4


- - Qualified employee benefit plans.

- - Trust companies or similar institutions, and charitable organizations that
  meet the definition in Section 501(c)(3) of the Internal Revenue Code.

- - Non-qualified deferred compensation plans whose participants are included in a
  qualified employee benefit plan described above.

- - State sponsored college savings plans established under Section 529 of the
  Internal Revenue Code.

- - Health Savings Accounts (HSAs) created pursuant to public law 108-173.

Additionally, if approved by the distributor, the following eligible
institutional investors may purchase Class R5 shares:

- - Institutional or corporate accounts above a threshold established by the
  distributor (currently $1 million per fund or $10 million in all RiverSource
  funds).

- - Bank Trust departments.

Class R shares generally are not available to retail non-retirement accounts,
traditional and Roth IRAs, Coverdell Educational Savings Accounts, SEPs, SAR-
SEPs, SIMPLE IRAs and individual 403(b) plans.

Class R shares may be purchased, sold or exchanged only through the distributor
or an authorized financial institution.

CLASS W SHARES.

The following eligible investors may purchase Class W shares:

- - Investors purchasing through authorized investment programs managed by
  investment professionals, including discretionary managed account programs.

Class W shares may be purchased, sold or exchanged only through the distributor
or an authorized financial institution.

Shares originally purchased in a discretionary managed account may continue to
be held in Class W outside of a discretionary managed account, but no additional
Class W purchases may be made and no exchanges to Class W shares of another fund
may be made outside of a discretionary managed account.

IN ADDITION, FOR CLASS I, CLASS R AND CLASS W SHARES, THE DISTRIBUTOR, IN ITS
SOLE DISCRETION, MAY ACCEPT OR AUTHORIZE FINANCIAL INSTITUTIONS TO ACCEPT
INVESTMENTS FROM OTHER PURCHASERS NOT LISTED ABOVE.

For more information, see the SAI.

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

S.5


SALES CHARGES

CLASS A -- INITIAL SALES CHARGE ALTERNATIVE:

Your purchase price for Class A shares is generally the net asset value (NAV)
plus a front-end sales charge. The distributor receives the sales charge and
re-allows a portion of the sales charge to the financial institution through
which you purchased the shares. The distributor retains the balance of the sales
charge. The distributor retains the full sales charge you pay when you purchase
shares of the fund directly (not through a separately authorized financial
institution). Sales charges vary depending on the amount of your purchase.

SALES CHARGE* FOR CLASS A SHARES

FOR FIXED INCOME FUNDS EXCEPT THOSE LISTED BELOW

<Table>
<Caption>
                                                                      MAXIMUM REALLOWANCE
                            AS A % OF             AS A % OF                AS A % OF
TOTAL MARKET VALUE       PURCHASE PRICE**    NET AMOUNT INVESTED         PURCHASE PRICE
- --------------------------------------------------------------------------------------------
                                                           
 Up to $49,999                 4.75%                 4.99%                    4.00%
 $50,000 -- $99,999            4.25                  4.44                     3.50
 $100,000 -- $249,999          3.50                  3.63                     3.00
 $250,000 -- $499,999          2.50                  2.56                     2.15
 $500,000 -- $999,999          2.00                  2.04                     1.75
 $1,000,000 or more            0.00                  0.00                     0.00***
</Table>

FOR RIVERSOURCE FLOATING RATE FUND, RIVERSOURCE INFLATION PROTECTED SECURITIES
FUND, RIVERSOURCE INTERMEDIATE TAX-EXEMPT FUND, RIVERSOURCE LIMITED DURATION
BOND FUND AND RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND

<Table>
<Caption>
                                                                      MAXIMUM REALLOWANCE
                            AS A % OF             AS A % OF                AS A % OF
TOTAL MARKET VALUE       PURCHASE PRICE**    NET AMOUNT INVESTED         PURCHASE PRICE
- --------------------------------------------------------------------------------------------
                                                           
 Up to $49,999                 3.00%                 3.09%                    2.50%
 $50,000 -- $99,999            3.00                  3.09                     2.50
 $100,000 -- $249,999          2.50                  2.56                     2.15
 $250,000 -- $499,999          2.00                  2.04                     1.75
 $500,000 -- $999,999          1.50                  1.52                     1.25
 $1,000,000 or more            0.00                  0.00                     0.00***
</Table>

  * Because of rounding in the calculation of the offering price, the portion of
    the sales charge retained by the distributor may vary and the actual sales
    charge you pay may be more or less than the sales charge calculated using
    these percentages.
 ** Purchase price includes the sales charge.
 ***Although there is no sales charge for purchases with a total market value
    over $1,000,000, and therefore no re-allowance, the distributor may pay a
    financial institution the following: a sales commission of up to 1.00% for a
    sale with a total market value of $1,000,000 to $2,999,999; a sales
    commission up to 0.50% for a sale of $3,000,000 to $9,999,999; and a sales
    commission up to 0.25% for a sale of $10,000,000 or more.

- --------------------------------------------------------------------------------
                                                                             S.6


INITIAL SALES CHARGE -- RIGHTS OF ACCUMULATION (ROA). You may be able to reduce
the sales charge on Class A shares, based on the combined market value of
accounts in your ROA group, as described below. The current market values of the
following investments are eligible to be added together for purposes of
determining the sales charge on your purchase:

- - Your current investment in a fund; and

- - Previous investments you and members of your household have made in Class A,
  Class B or Class C shares in the fund and other RiverSource funds, provided
  your investment was subject to a sales charge. Your household consists of you,
  your spouse or domestic partner and your unmarried children under age 21
  sharing a mailing address.

The following accounts are eligible to be included in determining the sales
charge on your purchase:

- - Individual or joint accounts;

- - Roth and traditional IRAs, SEPs, SIMPLEs and TSCAs, provided they are invested
  in Class A, Class B or Class C shares that were subject to a sales charge;

- - UGMA/UTMA accounts for which you, your spouse, or your domestic partner is
  parent or guardian of the minor child;

- - Revocable trust accounts for which you or a member of your household,
  individually, is the beneficial owner/grantor;

- - Accounts held in the name of your, your spouse's, or your domestic partner's
  sole proprietorship or single owner limited liability company or S
  corporation; and

- - Qualified retirement plan assets, provided that you are the sole owner of the
  business sponsoring the plan, are the sole participant (other than a spouse)
  in the plan, and have no intention of adding participants to the plan.

The following accounts are not eligible to be included in determining the sales
charge on your purchase:

- - Accounts of pension and retirement plans with multiple participants, such as
  401(k) plans (which are combined to reduce the sales charge for the entire
  pension or retirement plan and therefore are not used to reduce the sales
  charge for your individual accounts);

- - Investments in Class A shares where the sales charge is waived, for example,
  purchases through wrap accounts;

- - Investments in Class D, Class E, Class I, Class R2, Class R3, Class R4, Class
  R5, Class W or Class Y shares;

- - Investments in 529 plans, donor advised funds, variable annuities, variable
  life insurance products, wrap accounts or managed separate accounts; and

- - Charitable and irrevocable trust accounts.

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

S.7


If you purchase RiverSource fund shares through different financial
institutions, and you want to include those assets toward a reduced sales
charge, you must inform your financial institution in writing about the other
accounts when placing your purchase order. Contact your financial institution to
determine what information is required.

Unless you provide your financial institution in writing with information about
all of the accounts that may count toward a sales charge reduction, there can be
no assurance that you will receive all of the reductions for which you may be
eligible. You should request that your financial institution provide this
information to the fund when placing your purchase order.

For more information on rights of accumulation, please see the SAI.

INITIAL SALES CHARGE -- LETTER OF INTENT (LOI). Generally, if you intend to
invest $50,000 or more (including existing ROA) over a period of up to 13
months, you may be able to reduce the front-end sales charge(s) for investments
in Class A shares by completing and filing an LOI. The required form of LOI may
vary by financial institution. Existing ROA can be included in your LOI. Each
purchase of fund shares normally subject to an initial sales charge made during
the 13-month period will be made at the public offering price applicable to a
single transaction of the total dollar amount indicated by the LOI. Five percent
of the commitment amount will be placed in escrow. At the end of the 13-month
period, the LOI will end and the shares will be released from escrow. If you do
not invest the commitment amount by the end of the 13 months, the remaining
unpaid sales charge will be redeemed from the escrowed shares and the remaining
balance released from escrow.

Existing ROA Example. Shareholder currently has $60,000 ROA in RiverSource
funds. Shareholder completes an LOI to invest $100,000 in RiverSource funds (ROA
eligible accounts). Shareholder only needs to invest an additional $40,000 in
RiverSource funds' Class A shares in order to fulfill the LOI commitment and
receive reduced front-end sales charge(s) over the next 13 months.

Notification Obligation. You must request the reduced sales charge when you buy
shares. If you do not complete and file an LOI, or do not request the reduced
sales charge at the time of purchase, you will not be eligible for the reduced
sales charge. You should request that your financial institution provide this
information to the fund when placing your purchase order. For more detail on
LOIs, please contact your financial institution or see the SAI.

INITIAL SALES CHARGE -- WAIVERS OF THE SALES CHARGE FOR CLASS A SHARES. Sales
charges do not apply to:

- - current or retired Board members, officers or employees of RiverSource funds
  or RiverSource Investments or its affiliates, their spouses or domestic
  partners, children, parents and their spouse's or domestic partner's parents.

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

                                                                             S.8


- - current or retired Ameriprise Financial Services, Inc. (Ameriprise Financial
  Services) financial advisors, employees of financial advisors, their spouses
  or domestic partners, children, parents and their spouse's or domestic
  partner's parents.

- - registered representatives and other employees of financial institutions
  having a selling agreement with the distributor, including their spouses,
  domestic partners, children, parents and their spouse's or domestic partner's
  parents.

- - portfolio managers employed by subadvisers of the RiverSource funds, including
  their spouses or domestic partners, children, parents and their spouse's or
  domestic partner's parents.

- - retirement plans qualified or created under sections 401(a), 401(k), 403(b) or
  457 of the Internal Revenue Code, if those purchases are made through a
  broker, agent, or other financial institution.

- - direct rollovers from qualified employee benefit plans, provided that the
  rollover involves a transfer to Class A shares in the same fund.

- - purchases made:

  - with dividend or capital gain distributions from a fund or from the same
    class of another RiverSource fund;

  - through or under a wrap fee product or other investment product sponsored by
    a financial institution having a selling agreement with the distributor;

  - through state sponsored college savings plans established under Section 529
    of the Internal Revenue Code;

  - through bank trust departments.

- - shareholders whose original purchase was in a Strategist fund merged into a
  RiverSource fund in 2000.

The distributor may, in its sole discretion, authorize the waiver of sales
charges for additional purchases or categories of purchases. Policies related to
reducing or waiving the sales charge may be modified or withdrawn at any time.

Unless you provide your financial institution with information in writing about
all of the factors that may count toward a waiver of the sales charge, there can
be no assurance that you will receive all of the waivers for which you may be
eligible. You should request that your financial institution provide this
information to the fund when placing your purchase order.

Because the current prospectus is available on riversource.com free of charge,
RiverSource Investments does not separately disclose information regarding
breakpoint discounts on the website.

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

S.9


CLASS B AND CLASS C -- CONTINGENT DEFERRED SALES CHARGE ALTERNATIVE

FOR CLASS B, the CDSC is based on the sale amount and the number of years
between purchase and sale. The following table shows how CDSC percentages on
sales decline:

<Table>
<Caption>
IF THE SALE IS MADE DURING THE:                      THE CDSC PERCENTAGE RATE IS:*
                                                  
 First year                                                        5%
 Second year                                                       4%
 Third year                                                        4%
 Fourth year                                                       3%
 Fifth year                                                        2%
 Sixth year                                                        1%
 Seventh or eighth year                                            0%
</Table>

* Because of rounding in the calculation, the portion of the CDSC retained by
  the distributor may vary and the actual CDSC you pay may be more or less than
  the CDSC calculated using these percentages.

Although there is no front-end sales charge when you buy Class B shares, the
distributor pays a sales commission of 4% to financial institutions that sell
Class B shares. A portion of this commission may, in turn, be paid to your
financial advisor. The distributor receives any CDSC imposed when you sell your
Class B shares.

You may not make additional purchases of Class B shares if your ROA exceeds
$49,999.99.

Purchases made prior to May 21, 2005 age on a calendar year basis. Purchases
made beginning May 21, 2005 age on a daily basis. For example, a purchase made
on Nov. 12, 2004 completed its first year on Dec. 31, 2004 under calendar year
aging. However, a purchase made on Nov. 12, 2005 completed its first year on
Nov. 11, 2006 under daily aging.

Class B shares purchased prior to May 21, 2005 will convert to Class A shares in
the ninth calendar year of ownership. Class B shares purchased beginning May 21,
2005 will convert to Class A shares one month after the completion of the eighth
year of ownership.

FOR CLASS C, a 1% CDSC may be charged if you sell your shares within one year
after purchase. Although there is no front-end sales charge when you buy Class C
shares, the distributor pays a total amount up to 1% (including sales commission
and advance of service fees) to financial institutions that sell Class C shares.
See "Buying and Selling Shares -- Distribution and Service Fees." A portion of
this commission may, in turn, be paid to your financial advisor. The distributor
receives any CDSC imposed when you sell your Class C shares. You may not make
additional purchases of Class C shares if your ROA exceeds $999,999.99.

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

                                                                            S.10


For both Class B and Class C, if the amount you sell causes the value of your
investment to fall below the cost of the shares you have purchased, the CDSC
will be based on the lower of the cost of those shares purchased or market
value. Because the CDSC is imposed only on sales that reduce your total purchase
payments, you do not have to pay a CDSC on any amount that represents
appreciation in the value of your shares, income earned by your shares, or
capital gains. In addition, the CDSC on your sale, if any, will be based on your
oldest purchase payment. The CDSC on the next amount sold will be based on the
next oldest purchase payment.

EXAMPLE

Assume you had invested $10,000 in Class B shares and that your investment had
appreciated in value to $12,000 after 3 1/2 years, including reinvested
dividends and capital gain distributions. You could sell up to $2,000 worth of
shares without paying a CDSC ($12,000 current value less $10,000 purchase
amount). If you sold $2,500 worth of shares, the CDSC would apply to the $500
representing part of your original purchase price. The CDSC rate would be 3%
because the sale was made during the fourth year after the purchase.

CDSC -- WAIVERS OF THE CDSC FOR CLASS B SHARES. The CDSC will be waived on sales
of shares:

- - in the event of the shareholder's death;

- - held in trust for an employee benefit plan; or

- - held in IRAs or certain qualified plans, such as Keogh plans, tax-sheltered
  custodial accounts or corporate pension plans, provided that the shareholder
  is:

  - at least 59 1/2 years old AND

  - taking a retirement distribution (if the sale is part of a transfer to an
    IRA or qualified plan, or a custodian-to-custodian transfer, the CDSC will
    not be waived) OR

  - selling under an approved substantially equal periodic payment arrangement.

CDSC -- WAIVERS OF THE CDSC FOR CLASS C SHARES. The CDSC will be waived on sales
of shares in the event of the shareholder's death.

CLASS I, CLASS R2, CLASS R3, CLASS R4, CLASS R5 AND CLASS W -- NO SALES CHARGE.
For each of Class I, Class R2, Class R3, Class R4, Class R5 and Class W there is
no initial sales charge or CDSC.

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

S.11


OPENING AN ACCOUNT

Financial institutions are required by law to obtain certain personal
information from each person who opens an account in order to verify the
identity of the person. As a result, when you open an account you will be asked
to provide your name, permanent street address, date of birth, and Social
Security or Employer Identification number. You may also be asked for other
identifying documents or information. If you do not provide this information,
the financial institution through which you are investing in the fund may not be
able to open an account for you. If the financial institution through which you
are investing in the fund is unable to verify your identity, your account may be
closed, or other steps may be taken, as deemed appropriate.

When you buy shares, your order will be priced at the next NAV calculated after
your order is accepted by the fund or an authorized financial institution.

You may establish and maintain your account with an authorized financial
institution or directly with the fund. The fund may appoint servicing agents to
accept purchase orders and to accept exchange (and sale) orders on its behalf.
Accounts maintained by the fund will be supported by the fund's transfer agent.

METHODS OF PURCHASING SHARES

These methods of purchasing shares generally apply to Class A, Class B, and
Class C shares.

CLASS B SHARES FOR RIVERSOURCE FLOATING RATE FUND, RIVERSOURCE INFLATION
PROTECTED SECURITIES FUND, RIVERSOURCE INTERMEDIATE TAX-EXEMPT FUND, RIVERSOURCE
LIMITED DURATION BOND FUND AND RIVERSOURCE SHORT DURATION U.S. GOVERNMENT FUND
ARE CLOSED TO NEW INVESTORS AND NEW PURCHASES. EXISTING SHAREHOLDERS IN THESE
FUNDS MAY CONTINUE TO OWN CLASS B SHARES AND MAKE EXCHANGES INTO AND OUT OF
EXISTING ACCOUNTS WHERE CLASS B SHARES OF THESE FUNDS ARE MAINTAINED.

ACCOUNT ESTABLISHED WITH YOUR FINANCIAL INSTITUTION

ALL REQUESTS        The financial institution through which you buy shares may
                    have different policies not described in this prospectus,
                    including different minimum investment amounts and minimum
                    account balances.
- --------------------------------------------------------------------------------

ACCOUNT ESTABLISHED WITH THE FUND

BY MAIL             You or the financial institution through which you buy
                    shares may establish an account directly with the fund. To
                    establish an account in this fashion, complete a RiverSource
                    funds account application with your financial advisor or
                    investment professional, and mail the account application to
                    the address below. Account applications may be obtained at
- --------------------------------------------------------------------------------

- --------------------------------------------------------------------------------
                                                                            S.12


METHODS OF PURCHASING SHARES (CONTINUED)


ACCOUNT ESTABLISHED WITH THE FUND (CONT.)

BY MAIL (CONT.)
                    riversource.com or may be requested by calling (888) 791-
                    3380. Make your check payable to the fund. The fund does not
                    accept cash, credit card convenience checks, money orders,
                    traveler's checks, starter checks, third or fourth party
                    checks, or other cash equivalents.

                    Mail your check and completed application to:

                    REGULAR MAIL   RIVERSOURCE FUNDS
                                   P.O. BOX 8041
                                   BOSTON, MA 02266-8041

                    EXPRESS MAIL   RIVERSOURCE FUNDS
                                   C/O BFDS
                                   30 DAN ROAD
                                   CANTON, MA 02021-2809

                    If you already have an account, include your name, account
                    number and the name of the fund and class of shares you wish
                    to purchase along with your check. You can make scheduled
                    investments in the fund by moving money from your checking
                    account or savings account. See the Minimum Investment and
                    Account Balance chart below for more information regarding
                    scheduled investment plans.
- --------------------------------------------------------------------------------

BY WIRE OR ACH      Fund shares purchased in an account established and
                    maintained with the fund may be paid for by federal funds
                    wire. Before sending a wire, call (888) 791-3380 to notify
                    the fund's transfer agent of the wire and to receive further
                    instructions.

                    If you are establishing an account with a wire purchase, you
                    are required to send a signed account application to the
                    address above. Please include the wire control number or
                    your new account number on the application.

                    Your bank or financial institution may charge additional
                    fees for wire transactions.
- --------------------------------------------------------------------------------

BY EXCHANGE         Call (888) 791-3380 or send signed written instructions to
                    the address above.
- --------------------------------------------------------------------------------

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

S.13


MINIMUM INVESTMENT AND ACCOUNT BALANCE

<Table>
<Caption>
                       FOR ALL FUNDS,                       RIVERSOURCE FLOATING
                       CLASSES AND                          RATE FUND
                       ACCOUNTS EXCEPT                      RIVERSOURCE INFLATION
                       THOSE LISTED TO THE   TAX QUALIFIED  PROTECTED SECURITIES
                       RIGHT (NONQUALIFIED)  ACCOUNTS       FUND                       CLASS W
- ----------------------------------------------------------------------------------------------
                                                                           
INITIAL INVESTMENT     $2,000                $1,000         $5,000                     $500
- ----------------------------------------------------------------------------------------------
ADDITIONAL
   INVESTMENTS         $100                  $100           $100                       None
- ----------------------------------------------------------------------------------------------
ACCOUNT BALANCE*       $300                  None           $2,500                     $500
</Table>

  * If your fund account balance falls below the minimum account balance for any
    reason, including a market decline, you may be asked to increase it to the
    minimum account balance or establish a scheduled investment plan. If you do
    not do so within 30 days, your shares may be automatically redeemed and the
    proceeds mailed to you.
- --------------------------------------------------------------------------------

MINIMUM INVESTMENT AND ACCOUNT BALANCE -- SCHEDULED INVESTMENT PLANS

<Table>
<Caption>
                       FOR ALL FUNDS,                       RIVERSOURCE FLOATING
                       CLASSES AND                          RATE FUND
                       ACCOUNTS EXCEPT                      RIVERSOURCE INFLATION
                       THOSE LISTED TO THE   TAX QUALIFIED  PROTECTED SECURITIES
                       RIGHT (NONQUALIFIED)  ACCOUNTS       FUND                       CLASS W
- ----------------------------------------------------------------------------------------------
                                                                           
INITIAL INVESTMENT     $100                  $100           $5,000                     $500
- ----------------------------------------------------------------------------------------------
ADDITIONAL
   INVESTMENTS         $100                  $50            $100                       None
- ----------------------------------------------------------------------------------------------
ACCOUNT BALANCE**      None                  None           $2,500                     $500
</Table>

 ** If your fund account balance is below the minimum initial investment
    described above, you must make payments at least monthly.
- --------------------------------------------------------------------------------

These minimums may be waived for accounts that are managed by an investment
professional, for accounts held in approved discretionary or non-discretionary
wrap programs, for accounts that are part of an employer-sponsored retirement
plan, or for other account types if approved by the distributor.

The fund reserves the right to modify its minimum account requirements at any
time, with or without prior notice.

Please contact your financial institution for information regarding wire or
electronic funds transfer.

IMPORTANT: Payments sent by electronic fund transfers (ACH), a bank
authorization or check that are not guaranteed may take up to 10 days to clear.
If you request a sale within 10 days of purchase, this may cause your sale
request to fail to process if the requested amount includes unguaranteed funds.

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

                                                                            S.14


EXCHANGING OR SELLING SHARES

You may exchange or sell shares by having your financial institution process
your transaction. If your account is maintained directly with your financial
institution, you must contact that financial institution to exchange or sell
shares of the fund. If your account was established with the fund, there are a
variety of methods you may use to exchange or sell shares of the fund.

WAYS TO REQUEST AN EXCHANGE OR SALE OF SHARES

ACCOUNT ESTABLISHED WITH YOUR FINANCIAL INSTITUTION

ALL REQUESTS        You can exchange or sell shares by having your financial
                    institution process your transaction. The financial
                    institution through which you purchased shares may have
                    different policies not described in this prospectus,
                    including different transaction limits, exchange policies
                    and sale procedures.
- --------------------------------------------------------------------------------

ACCOUNT ESTABLISHED WITH THE FUND

BY MAIL             Mail your exchange or sale request to:

                    REGULAR MAIL   RIVERSOURCE FUNDS
                                   P.O. BOX 8041
                                   BOSTON, MA 02266-8041

                    EXPRESS MAIL   RIVERSOURCE FUNDS
                                   C/O BFDS
                                   30 DAN ROAD
                                   CANTON, MA 02021-2809

                    Include in your letter:

                    - your name

                    - the name of the fund(s)

                    - your account number

                    - the class of shares to be exchanged or sold

                    - your Social Security number or Employer Identification
                      number

                    - the dollar amount or number of shares you want to exchange
                      or sell

                    - specific instructions regarding delivery or exchange
                      destination

                    - signature(s) of registered account owner(s)

                    - any special documents the transfer agent may require in
                      order to process your order
- --------------------------------------------------------------------------------

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

S.15


WAYS TO REQUEST AN EXCHANGE OR SALE OF SHARES (CONTINUED)


ACCOUNT ESTABLISHED WITH THE FUND (CONT.)

BY MAIL (CONT.)

                    Corporate, trust or partnership accounts may need to send
                    additional documents.

                    Payment will be mailed to the address of record and made
                    payable to the names listed on the account, unless your
                    request specifies differently and is signed by all owners.

                    A Medallion Signature Guarantee is required if:

                    - Amount is over $50,000.

                    - You want your check made payable to someone other than
                      yourself.

                    - Your address has changed within the last 30 days.

                    - You want the check mailed to an address other than the
                      address of record.

                    - You want the proceeds sent to a bank account not on file.

                    - You are the beneficiary of the account and the account
                      owner is deceased (additional documents may be required).

                    A Medallion Signature Guarantee assures that a signature is
                    genuine and not a forgery. The financial institution
                    providing the Guarantee is financially liable for the
                    transaction if the signature is a forgery. Eligible
                    guarantors include commercial banks, trust companies,
                    savings associations, and credit unions as defined by the
                    Federal Deposit Insurance Act. Note: A guarantee from a
                    notary public is not acceptable.

                    NOTE: Any express mail delivery charges you pay will vary
                    depending on domestic or international delivery
                    instructions.
- --------------------------------------------------------------------------------

BY TELEPHONE        Call (888) 791-3380. Unless you elect not to have telephone
                    exchange and sale privileges, they will automatically be
                    available to you. Reasonable procedures will be used to
                    confirm authenticity of telephone exchange or sale requests.
                    Telephone privileges may be modified or discontinued at any
                    time. Telephone exchange and sale privileges automatically
                    apply to all accounts except custodial, corporate or
                    qualified retirement accounts. You may request that these
                    privileges NOT apply by writing to the address above.

                    Payment will be mailed to the address of record and made
                    payable to the names listed on the account.

                    Telephone sale requests are limited to $100,000 per day.
- --------------------------------------------------------------------------------

- --------------------------------------------------------------------------------
                                                                            S.16


WAYS TO REQUEST AN EXCHANGE OR SALE OF SHARES (CONTINUED)


ACCOUNT ESTABLISHED WITH THE FUND (CONT.)

BY WIRE OR ACH      You can wire money from your fund account to your bank
                    account. Make sure we have your bank account information on
                    file. If we do not have this information, you will need to
                    send written instructions with your bank's name and a voided
                    check or savings account deposit slip.

                    Call (888) 791-3380 or send a letter of instruction, with a
                    Medallion Signature Guarantee if required, to the address
                    above.

                    A service fee may be charged against your account for each
                    wire sent.

                    Minimum amount: $100

                    Your bank or financial institution may charge additional
                    fees for wire transactions.
- --------------------------------------------------------------------------------

BY SCHEDULED
PAYOUT PLAN         You may elect to receive regular periodic payments through
                    an automatic sale of shares. See the SAI for more
                    information.
- --------------------------------------------------------------------------------

EXCHANGES

Generally, you may exchange your fund shares for shares of the same class of any
other publicly offered RiverSource fund without a sales charge. For complete
information on the fund you are exchanging into, including fees and expenses,
read that fund's prospectus carefully. Your exchange will be priced at the next
NAV calculated after your transaction request is received in good order. You may
be subject to a sales charge if you exchange from a money market fund into an
equity or fixed income fund.

SHORT-TERM TRADING AND OTHER SO-CALLED MARKET TIMING PRACTICES ARE FREQUENT
TRADING PRACTICES BY CERTAIN SHAREHOLDERS INTENDED TO PROFIT AT THE EXPENSE OF
OTHER SHAREHOLDERS BY SELLING SHARES OF A FUND SHORTLY AFTER PURCHASE. MARKET
TIMING MAY ADVERSELY IMPACT A FUND'S PERFORMANCE BY PREVENTING THE INVESTMENT
MANAGER FROM FULLY INVESTING THE ASSETS OF THE FUND, DILUTING THE VALUE OF
SHARES HELD BY LONG-TERM SHAREHOLDERS, OR INCREASING THE FUND'S TRANSACTION
COSTS.

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

S.17


FUNDS THAT INVEST IN SECURITIES THAT TRADE INFREQUENTLY MAY BE VULNERABLE TO
MARKET TIMERS WHO SEEK TO TAKE ADVANTAGE OF INEFFICIENCIES IN THE SECURITIES
MARKETS. FUNDS THAT INVEST IN SECURITIES THAT TRADE ON OVERSEAS SECURITIES
MARKETS MAY BE VULNERABLE TO MARKET TIMERS WHO SEEK TO TAKE ADVANTAGE OF CHANGES
IN THE VALUES OF SECURITIES BETWEEN THE CLOSE OF OVERSEAS MARKETS AND THE CLOSE
OF U.S. MARKETS, WHICH IS GENERALLY THE TIME AT WHICH A FUND'S NAV IS
CALCULATED. TO THE EXTENT THAT A FUND HAS SIGNIFICANT HOLDINGS OF HIGH YIELD
BONDS, TAX-EXEMPT SECURITIES OR FOREIGN SECURITIES, THE RISKS OF MARKET TIMING
MAY BE GREATER FOR THE FUND THAN FOR OTHER FUNDS. SEE "PRINCIPAL INVESTMENT
STRATEGIES" FOR A DISCUSSION OF THE TYPES OF SECURITIES IN WHICH YOUR FUND
INVESTS.

SEE "VALUING FUND SHARES" FOR A DISCUSSION OF THE RIVERSOURCE FUNDS' POLICY ON
FAIR VALUE PRICING, WHICH IS INTENDED, IN PART, TO REDUCE THE FREQUENCY AND
EFFECT OF MARKET TIMING.

THE RIVERSOURCE FUNDS' BOARD HAS ADOPTED A POLICY THAT IS DESIGNED TO DETECT AND
DETER MARKET TIMING THAT MAY BE HARMFUL TO THE FUNDS. EACH FUND SEEKS TO ENFORCE
THIS POLICY THROUGH ITS SERVICE PROVIDERS AS FOLLOWS:

- - The fund tries to distinguish market timing from trading that it believes is
  not harmful, such as periodic rebalancing for purposes of asset allocation or
  dollar cost averaging or other purchase and exchange transactions not believed
  to be inconsistent with the best interest of fund shareholders or the Board's
  policy. The fund uses a variety of techniques to monitor for and detect
  abusive trading practices. These techniques may vary depending on the type of
  fund, the class of shares and where the shares are maintained. Under the
  fund's procedures, there is no set number of transactions in the fund that
  constitutes market timing. Even one purchase and subsequent sale by related
  accounts may be market timing. Generally, the fund seeks to restrict the
  exchange privilege of an investor who makes more than three exchanges into or
  out of the fund in any 90-day period. Accounts held by a retirement plan or a
  financial institution for the benefit of its participants or clients, which
  typically engage in daily transactions, are not subject to this limit,
  although the fund may seek the assistance of financial institutions in
  applying similar restrictions on their participants or clients. The Fund's
  ability to monitor and discourage abusive trading practices in omnibus
  accounts is more limited.

- - The fund may rely on the monitoring policy of a financial institution, for
  example, a retirement plan administrator or similar financial institution
  authorized to distribute the funds, if it determines the policy and procedures
  of such financial institutions are sufficient to protect the fund and its
  shareholders.

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

                                                                            S.18


- - If an investor's trading activity is determined to be market timing or
  otherwise harmful to existing shareholders, the fund reserves the right to
  modify or discontinue the investor's exchange privilege or reject the
  investor's purchases or exchanges, including purchases or exchanges accepted
  by a financial institution. The fund may treat accounts it believes to be
  under common control as a single account for these purposes, although it may
  not be able to identify all such accounts.

- - Although the fund does not knowingly permit market timing, it cannot guarantee
  that it will be able to identify and restrict all short-term trading activity.
  The fund receives purchase and sale orders through financial institutions
  where market timing activity may not always be successfully detected.

Other exchange policies:

- - Exchanges must be made into the same class of shares of the new fund.

- - Exchanges into RiverSource Tax-Exempt Money Market Fund may be made only from
  Class A shares.

- - If your exchange creates a new account, it must satisfy the minimum investment
  amount for new purchases.

- - Once the fund receives your exchange request, you cannot cancel it.

- - Shares of the new fund may not be used on the same day for another exchange or
  sale.

- - Shares of the Class W originally purchased, but no longer held in a
  discretionary managed account, may not be exchanged for Class W shares of
  another fund. You may continue to hold these shares in the fund. Changing your
  investment to a different fund will be treated as a sale and purchase, and you
  will be subject to applicable taxes on the sale and sales charges on the
  purchase of the new fund.

SELLING SHARES

You may sell your shares at any time. The payment will be sent within seven days
after your request is received in good order.

When you sell shares, the amount you receive may be more or less than the amount
you invested. Your sale price will be the next NAV calculated after your request
is received in good order, minus any applicable CDSC.

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

S.19


REPURCHASES. You can change your mind after requesting a sale and use all or
part of the sale proceeds to purchase new shares in the same account, fund and
class from which you sold. If you reinvest in Class A, you will purchase the new
shares at NAV, up to the amount of the sale proceeds, instead of paying a sales
charge on the date of a new purchase. If you reinvest in Class B or Class C, any
CDSC you paid on the amount you are reinvesting also will be reinvested. In
order for you to take advantage of this repurchase waiver, you must notify your
financial institution within 90 days of the date your sale request was
processed. Contact your financial institution for information on required
documentation. The repurchase privilege may be modified or discontinued at any
time and use of this option may have tax consequences.

The fund reserves the right to redeem in kind.

For more details and a description of other sales policies, please see the SAI.

VALUING FUND SHARES

For classes of shares sold with an initial sales charge, the public offering or
purchase price is the net asset value plus the sales charge. For funds or
classes of shares sold without an initial sales charge, the public offering
price is the NAV.

Orders in good form are priced at the NAV next determined after you place your
order. Good form or good order means that your instructions have been received
in the form required by the fund. This may include, for example, providing the
fund name and account number, the amount of the transaction and all required
signatures. For more information, contact your financial institution.

The NAV is the value of a single share of the fund. The NAV is determined by
dividing the value of the fund's assets, minus any liabilities, by the number of
shares outstanding. The NAV is calculated as of the close of business on the New
York Stock Exchange (NYSE), normally 4:00 p.m. Eastern time, on each day that
the NYSE is open. Securities are valued primarily on the basis of market
quotations and floating rate loans are valued primarily on the basis of
indicative bids. Both market quotations and indicative bids are obtained from
outside pricing services approved and monitored under procedures adopted by the
Board. Certain short-term securities with maturities of 60 days or less are
valued at amortized cost.

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

                                                                            S.20


When reliable market quotations or indicative bids are not readily available,
investments are priced at fair value based on procedures adopted by the Board.
These procedures are also used when the value of an investment held by a fund is
materially affected by events that occur after the close of a securities market
but prior to the time as of which the fund's NAV is determined. Valuing
investments at fair value involves reliance on judgment. The fair value of an
investment is likely to differ from any available quoted or published price. To
the extent that a fund has significant holdings of high yield bonds, floating
rate loans, tax-exempt securities or foreign securities that may trade
infrequently, fair valuation may be used more frequently than for other funds.
The RiverSource funds use an unaffiliated service provider to assist in
determining fair values for foreign securities.

Foreign investments are valued in U.S. dollars. Some of a fund's securities may
be listed on foreign exchanges that trade on weekends or other days when the
fund does not price its shares. In that event, the NAV of the fund's shares may
change on days when shareholders will not be able to purchase or sell the fund's
shares.

DISTRIBUTIONS AND TAXES

As a shareholder you are entitled to your share of your fund's net income and
net gains. Each fund distributes dividends and capital gains to qualify as a
regulated investment company and to avoid paying corporate income and excise
taxes.

DIVIDENDS AND CAPITAL GAIN DISTRIBUTIONS

Your fund's net investment income is distributed to you as dividends. Dividends
may be composed of qualified dividend income, which is eligible for preferential
tax rates under current tax law, as well as other ordinary dividend income,
which may include dividends which are non-qualified dividends, interest income
and short-term capital gains. Because of the types of income earned by fixed
income funds, it is unlikely the funds will distribute qualified dividend
income. Generally, capital gains are realized when a security is sold for a
higher price than was paid for it. Generally, capital losses are realized when a
security is sold for a lower price than was paid for it. Typically, each
realized capital gain or loss is long-term or short-term depending on the length
of time the fund held the security. Realized capital gains and losses offset
each other. The fund offsets any net realized capital gains by any available
capital loss carryovers. Net short-term capital gains, if any, are included in
net investment income and are taxable as ordinary income when distributed to the
shareholder. Net realized long-term capital gains, if any, are distributed by
the end of the calendar year as capital gain distributions. If the fund's
distributions exceed its current and accumulated earnings and profits, that
portion of the fund's distributions will be treated as a return of capital to
the shareholders to the extent of their basis in their shares. A return of
capital will generally not be taxable; however, any amounts received in excess
of basis are treated as capital gain. Forms 1099 sent to shareholders report any
return of capital.

- --------------------------------------------------------------------------------
S.21


Certain derivative instruments subject the fund to special tax rules, the effect
of which may be to accelerate income to the fund, defer fund losses, cause
adjustments in the holding periods of fund securities, convert capital gains
into ordinary income and convert short-term capital losses into long-term
capital losses. These rules could therefore affect the amount, timing and
character of distributions to shareholders.

REINVESTMENTS

Dividends and capital gain distributions are automatically reinvested in
additional shares in the same class of the fund unless you request distributions
in cash. The financial institution through which you purchased shares may have
different policies.

Distributions are reinvested at the next calculated NAV after the distribution
is paid. If you choose cash distributions, you will receive cash only for
distributions declared after your request has been processed.

TAXES

If you buy shares shortly before the record date of a distribution, you may pay
taxes on money earned by the fund before you were a shareholder. You will pay
the full pre-distribution price for the shares, then receive a portion of your
investment back as a distribution, which may be taxable.

For tax purposes, an exchange is considered a sale and purchase, and may result
in a gain or loss. A sale is a taxable transaction. Generally, if you sell
shares for less than their cost, the difference is a capital loss or if you sell
shares for more than their cost, the difference is a capital gain. Your gain may
be short term (for shares held for one year or less) or long term (for shares
held for more than one year).

You may not create a tax loss or reduce a tax gain, based on paying a sales
charge, by exchanging shares before the 91(st) day after the day of purchase. If
you buy Class A shares and exchange into another fund before the 91(st) day
after the day of purchase, you may not be able to include the sales charge in
your calculation of tax gain or loss on the sale of the first fund you
purchased. The sales charge may be included in the calculation of your tax gain
or loss on a subsequent sale of the second fund you purchased. For more
information, see the SAI.

FOR TAXABLE FUNDS. Distributions related to shares not held in IRAs or other
retirement accounts are subject to federal income tax and may be subject to
state and local taxes in the year they are declared. You must report
distributions on your tax returns, even if they are reinvested in additional
shares.

Shares held in an IRA or qualified retirement account are generally subject to
different tax rules. Taking a distribution from your IRA or qualified retirement
plan may subject you to federal taxes, withholding, penalties and reporting
requirements. Please consult your tax advisor.

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

                                                                            S.22


Income received by a fund may be subject to foreign tax and withholding. Tax
conventions between certain countries and the U.S. may reduce or eliminate these
taxes.

FOR RIVERSOURCE INFLATION PROTECTED SECURITIES FUND. Any increase in principal
for an inflation-protected security resulting from inflation adjustments is
considered by Internal Revenue Service regulations to be taxable income in the
year it occurs. The fund will distribute both interest income and the income
attributable to principal adjustments, both of which are taxable to
shareholders.

FOR TAX-EXEMPT FUNDS. Dividends distributed from interest earned on tax-exempt
securities (exempt-interest dividends) are exempt from federal income taxes but
may be subject to state and local taxes and potentially the alternative minimum
tax. Dividends distributed from net capital gains, if any, and other income
earned are not exempt from federal income taxes. Any taxable distributions are
taxable in the year the fund declares them regardless of whether you take them
in cash or reinvest them.

Interest on certain private activity bonds is a preference item for purposes of
the individual and corporate alternative minimum tax. To the extent the fund
earns such income, it will flow through to its shareholders and may affect those
shareholders who are subject to the alternative minimum tax. See the SAI for
more information.

Because interest on municipal bonds and notes is tax-exempt for federal income
tax purposes, any interest on money you borrow that is used directly or
indirectly to purchase fund shares is not deductible on your federal income tax
return. You should consult a tax advisor regarding its deductibility for state
and local income tax purposes.

IMPORTANT: This information is a brief and selective summary of some of the tax
rules that apply to an investment in a fund. Because tax matters are highly
individual and complex, you should consult a qualified tax advisor.

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

S.23


GENERAL INFORMATION

AVAILABILITY AND TRANSFERABILITY OF FUND SHARES

Please consult with your financial institution to determine the availability of
the RiverSource funds. RiverSource funds may only be purchased or sold directly
or through financial institutions authorized by the distributor to offer the
RiverSource funds. NOT ALL FINANCIAL INSTITUTIONS ARE AUTHORIZED TO SELL THE
FUNDS. If you set up an account at a financial institution that does not have,
and is unable to obtain, a selling agreement with the distributor of the
RiverSource funds, you will not be able to transfer RiverSource fund holdings to
that account. In that event, you must either maintain your RiverSource fund
holdings with your current financial institution, find another financial
institution with a selling agreement, or sell your shares, paying any applicable
CDSC. Please be aware that transactions in taxable accounts are taxable events
and may result in income tax liability.

ADDITIONAL SERVICES AND COMPENSATION

In addition to acting as the fund's investment manager, RiverSource Investments
and its affiliates also receive compensation for providing other services to the
funds.

Administration Services. Ameriprise Financial, 200 Ameriprise Financial Center,
Minneapolis, Minnesota 55474, provides or compensates others to provide
administrative services to the RiverSource funds. These services include
administrative, accounting, treasury, and other services. Fees paid by a fund
for these services are included under "Other expenses" in the expense table
under "Fees and Expenses."

Custody Services. Ameriprise Trust Company, 200 Ameriprise Financial Center,
Minneapolis, Minnesota 55474, provides custody services to all but a limited
number of the RiverSource funds, for which U.S. Bank National Association, The
Bank of New York or JP Morgan Chase Bank, N.A. provide custody services. In
addition to paying the custodian for these services, the RiverSource funds pay
for certain transaction fees and out-of-pocket expenses incurred while providing
custody services to the funds. Fees paid by a fund for these services are
included under "Other expenses" in the expense table under "Fees and Expenses."

Distribution and Shareholder Services. RiverSource Distributors, Inc., 50611
Ameriprise Financial Center, Minneapolis, Minnesota 55474 (the distributor or
RiverSource Distributors), provides underwriting and distribution services to
the RiverSource funds. Under the Distribution Agreement and related distribution
and shareholder servicing plans, the distributor receives distribution and
shareholder servicing fees. The distributor may retain a portion of these fees
to support its distribution and shareholder servicing activity. The distributor
re-allows the remainder of these fees (or the full fee) to the financial
institutions that sell fund shares and provide services to shareholders. Fees
paid by a fund for these services are set forth under "Distribution (12b-1)
fees" in the expense table under "Fees

- --------------------------------------------------------------------------------
                                                                            S.24


and Expenses." More information on how these fees are used is set forth under
"Investment Options -- Classes of Shares" and in the SAI. The distributor also
administers any sales charges paid by an investor at the time of purchase or at
the time of sale. See "Shareholder Fees (fees paid directly from your
investment)" under "Fees and Expenses" for the scheduled sales charge of each
share class. See "Buying and Selling Shares, Sales Charges" for variations in
the scheduled sales charges, and for how these sales charges are used by the
distributor. See "Other Investment Strategies and Risks" for the RiverSource
funds' policy regarding directed brokerage.

Transfer Agency Services. RiverSource Service Corporation, 734 Ameriprise
Financial Center, Minneapolis, Minnesota 55474 (the transfer agent or
RiverSource Service Corporation), provides or compensates others to provide
transfer agency services to the RiverSource funds. The RiverSource funds pay the
transfer agent a fee that varies by class, as set forth in the SAI, and
reimburses the transfer agent for its out-of-pocket expenses incurred while
providing these transfer agency services to the funds. Fees paid by a fund for
these services are included under "Other expenses" in the expense table under
"Fees and Expenses." RiverSource Service Corporation pays a portion of these
fees to financial institutions that provide sub-recordkeeping and other services
to fund shareholders. The SAI provides additional information about the services
provided and the fee schedules for the transfer agent agreements.

Plan Administration Services. Under a Plan Administration Services Agreement the
fund pays for plan administration services, including services such as
implementation and conversion services, account set-up and maintenance,
reconciliation and account recordkeeping, education services and administration
to various plan types, including 529 plans, retirement plans and Health Savings
Accounts (HSAs). Fees paid by a fund for these services are included under
"Other expenses" in the expense table under "Fees and Expenses."

PAYMENTS TO FINANCIAL INSTITUTIONS

The distributor and its affiliates make or support additional cash payments out
of their own resources (including profits earned from providing services to the
fund) to financial institutions, including inter-company allocation of resources
or payments to affiliated broker-dealers, in connection with agreements between
the distributor and financial institutions pursuant to which these financial
institutions sell fund shares and provide services to their clients who are
shareholders of the fund. These payments and intercompany allocations
(collectively, "payments") do not change the price paid by investors in the fund
or fund shareholders for the purchase or ownership of fund shares of the fund,
and these payments are not reflected in the fees and expenses of the fund, as
they are not paid by the fund.

In exchange for these payments, a financial institution may elevate the
prominence or profile of the fund within the financial institution's
organization, and may

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

S.25


provide the distributor and its affiliates with preferred access to the
financial institution's registered representatives or preferred access to the
financial institution's customers. These arrangements are sometimes referred to
as marketing and/or sales support payments, program and/or shareholder servicing
payments, or revenue sharing payments. These arrangements create potential
conflicts of interest between a financial institution's pecuniary interest and
its duties to its customers, for example, if the financial institution receives
higher payments from the sale of a certain fund than it receives from the sale
of other funds, the financial institution or its representatives may be incented
to recommend or sell shares of the fund where it receives or anticipates
receiving the higher payment instead of other investment options that may be
more appropriate for the customer. Employees of Ameriprise Financial and its
affiliates, including employees of affiliated broker-dealers, may be separately
incented to recommend or sell shares of the fund, as employee compensation and
business unit operating goals at all levels are tied to the company's success.
Certain employees, directly or indirectly, may receive higher compensation and
other benefits as investment in the fund increases. In addition, management,
sales leaders and other employees may spend more of their time and resources
promoting Ameriprise Financial and its subsidiary companies, including
RiverSource Investments and the distributor, and the products they offer,
including the fund.

These payments are typically negotiated based on various factors including, but
not limited to, the scope and quality of the services provided by the financial
institution, its reputation in the industry, its ability to attract and retain
assets, its access to target markets, its customer relationships, the profile
the fund may obtain within the financial institution, and the access the
distributor or other representatives of the fund may have within the financial
institution for advertisement, training or education, including opportunities to
present at or sponsor conferences for the registered representatives of the
financial institution and its customers.

These payments are usually calculated based on a percentage of fund assets owned
through the financial institution and/or as a percentage of fund sales
attributable to the financial institution. Certain financial institutions
require flat fees instead of, or in addition to, these asset-based fees as
compensation for including or maintaining a fund on their platforms, and, in
certain situations, may require the reimbursement of ticket or operational
charges -- fees that a financial institution charges its registered
representatives for effecting transactions in the fund. The amount of payment
varies by financial institution (e.g., initial platform set-up fees, ongoing
maintenance or service fees, or asset or sales based fees). The amount of
payments also varies by the type of sale. For instance, purchases of one fund
may warrant a greater or lesser amount of payments than purchases of another
fund. Additionally, sale and maintenance of shares on a stand alone basis may
result in a greater or lesser amount of payments than the sale and maintenance
of shares made through a plan, wrap or other fee-based program. Payments to
affiliates may include

- --------------------------------------------------------------------------------
                                                                            S.26


payments as compensation to employees of RiverSource Investments who are
licensed by the distributor in respect of certain sales and solicitation
activity on behalf of the fund. These payments may be and often are significant.
Additional information concerning the amount and calculation of these payments
is available in the fund's SAI.

Payments to affiliated broker-dealers are within the range of the payments the
distributor pays to similarly-situated third party financial institutions and
the payments such affiliated broker-dealers receive from third party fund
sponsors related to the sale of their sponsored funds. However, because of the
large amount of RiverSource fund assets (in aggregate) currently held in
customer accounts of the affiliated broker-dealers, the distributor and its
affiliates, in the aggregate, pay significantly more in absolute dollars than
other third-party fund sponsors pay to the affiliated broker-dealers for the
sale and servicing of their sponsored funds. This level of payment creates
potential conflicts of interest which the affiliated broker-dealers seek to
mitigate by disclosure and implementation of internal controls, as well as the
rules and regulations of applicable regulators.

From time to time, to the extent permitted by SEC and FINRA rules and by other
applicable laws and regulations, the distributor and its affiliates may make
other reimbursements or payments to financial institutions or their registered
representatives, including non-cash compensation, in the form of gifts of
nominal value, occasional meals, tickets, or other entertainment, support for
due diligence trips, training and educational meetings or conference
sponsorships, support for recognition programs, and other forms of non-cash
compensation permissible under regulations to which these financial institutions
and their representatives are subject. To the extent these are made as payments
instead of reimbursement, they may provide profit to the financial institution
to the extent the cost of such services was less than the actual expense of the
service.

The financial institution through which you are purchasing or own shares of the
fund has been authorized directly or indirectly by the distributor to sell the
fund and/or to provide services to you as a shareholder of the fund. Investors
and current shareholders may wish to take such payment arrangements into account
when considering and evaluating any recommendations they receive relating to
fund shares. If you have questions regarding the specific details regarding the
payments your financial institution may receive from the distributor or its
affiliates related to your purchase or ownership of the fund, please contact
your financial institution. The SAI contains additional detail regarding
payments made by the distributor to financial institutions.

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

S.27


The payments described in this section are in addition to fees paid by the fund
to the distributor under 12b-1 plans, which fees may be used to compensate
financial institutions for the distribution of fund shares and the servicing of
fund shareholders, or paid by the fund to the transfer agent under the transfer
agent agreement or plan administration agreement, which fees may be used to
support networking or servicing fees to compensate financial institutions for
supporting shareholder account maintenance, sub-accounting, plan recordkeeping
or other services provided directly by the financial institution to shareholders
or plans and plan participants, including retirement plans, 529 plans, Health
Savings Account plans, or other plans, where participants beneficially own
shares of the fund.

Financial institutions may separately charge you additional fees. See "Buying
and Selling Shares."

ADDITIONAL MANAGEMENT INFORMATION

MANAGER OF MANAGERS EXEMPTION. The RiverSource funds have received an order from
the Securities and Exchange Commission that permits RiverSource Investments,
subject to the approval of the Board, to appoint a subadviser or change the
terms of a subadvisory agreement for a fund without first obtaining shareholder
approval. The order permits the fund to add or change unaffiliated subadvisers
or change the fees paid to subadvisers from time to time without the expense and
delays associated with obtaining shareholder approval of the change.

Before certain fixed income funds may rely on the order, holders of a majority
of the fund's outstanding voting securities will need to approve operating the
fund in this manner. There is no assurance shareholder approval will be
received, and no changes will be made without shareholder approval until that
time. For more information, see the SAI.

RiverSource Investments or its affiliates may have other relationships,
including significant financial relationships, with current or potential
subadvisers or their affiliates, which may create a conflict of interest. In
making recommendations to the Board to appoint or to change a subadviser, or to
change the terms of a subadvisory agreement, RiverSource Investments does not
consider any other relationship it or its affiliates may have with a subadviser,
and RiverSource Investments discloses the nature of any material relationships
it has with a subadviser to the Board.

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

                                                                            S.28


AFFILIATED PRODUCTS. RiverSource Investments also serves as investment manager
to RiverSource funds which are structured to provide asset-allocation services
to shareholders of those funds by investing in shares of other RiverSource funds
(Funds of Funds) and to discretionary managed accounts that invest exclusively
in RiverSource funds (collectively referred to as "affiliated products"). These
affiliated products, individually or collectively, may own a significant
percentage of the fund's outstanding shares. The fund may experience relatively
large purchases or redemptions from the affiliated products. Although
RiverSource Investments may seek to minimize the impact of these transactions,
for example, by structuring them over a reasonable period of time or through
other measures, the fund may experience increased expenses as it buys and sells
securities to manage transactions for the affiliated products. In addition,
because the affiliated products may own a substantial portion of the fund, a
redemption by one or more affiliated products could cause the fund's expense
ratio to increase as the fund's fixed costs would be spread over a smaller asset
base. RiverSource Investments monitors expense levels and is committed to
offering funds that are competitively priced. RiverSource Investments reports to
the Board on the steps it has taken to manage any potential conflicts. See the
SAI for information on the percent of the fund owned by affiliated products.

CASH RESERVES. A fund may invest its daily cash balance in RiverSource Short-
Term Cash Fund (Short-Term Cash Fund), a money market fund established for the
exclusive use of the RiverSource funds and other institutional clients of
RiverSource Investments. While Short-Term Cash Fund does not pay an advisory fee
to RiverSource Investments, it does incur other expenses, and is expected to
operate at a very low expense ratio. A fund will invest in Short-Term Cash Fund
only to the extent it is consistent with the fund's investment objectives and
policies. Short-Term Cash Fund is not insured or guaranteed by the FDIC or any
other government agency.

FUND HOLDINGS DISCLOSURE. The Board has adopted policies and procedures that
govern the timing and circumstances of disclosure to shareholders and third
parties of information regarding the securities owned by a fund. A description
of these policies and procedures is included in the SAI.

LEGAL PROCEEDINGS. Ameriprise Financial and certain of its affiliates have
historically been involved in a number of legal, arbitration and regulatory
proceedings, including routine litigation, class actions, and governmental
actions, concerning matters arising in connection with the conduct of their
business activities. Ameriprise Financial believes that the fund is not
currently the subject of, and that neither Ameriprise Financial nor any of its
affiliates are the subject of, any pending legal, arbitration or regulatory
proceedings that are likely to have a material adverse effect on the fund or the
ability of Ameriprise Financial or its affiliates to perform under their
contracts with the fund. Information regarding certain pending and settled legal
proceedings may be found in the fund's shareholder reports and in the SAI.
Additionally, Ameriprise Financial is required

- --------------------------------------------------------------------------------
S.29


to make 10-Q, 10-K and, as necessary, 8-K filings with the Securities and
Exchange Commission on legal and regulatory matters that relate to Ameriprise
Financial and its affiliates. Copies of these filings may be obtained by
accessing the SEC website at www.sec.gov.

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

                                                                            S.30


RiverSource Funds can be purchased from authorized financial institutions. The
fund can be found under the "RiverSource" banner in most mutual fund quotations.

Additional information about the fund and its investments is available in the
fund's SAI, and annual and semiannual reports to shareholders. In the fund's
annual report, you will find a discussion of market conditions and investment
strategies that significantly affected the fund's performance during its most
recent fiscal year. The SAI is incorporated by reference in this prospectus. For
a free copy of the SAI, the annual report, or the semiannual report, or to
request other information about the fund, contact RiverSource Funds or your
financial institution. To make a shareholder inquiry, contact the financial
institution through whom you purchased the fund.

RiverSource Funds
734 Ameriprise Financial Center
Minneapolis, MN 55474
(888) 791-3380

RiverSource Funds information available at RiverSource Investments website
address:
riversource.com/funds

You may review and copy information about the fund, including the SAI, at the
Securities and Exchange Commission's (Commission) Public Reference Room in
Washington, D.C. (for information about the public reference room call
1-202-551-8090). Reports and other information about the fund are available on
the EDGAR Database on the Commission's Internet site at www.sec.gov. Copies of
this information may be obtained, after paying a duplicating fee, by electronic
request at the following E-mail address: publicinfo@sec.gov, or by writing to
the Public Reference Section of the Commission, 100 F Street, N.E., Washington,
D.C. 20549-0102.

Investment Company Act File #811-4260

<Table>
                                                                 
TICKER SYMBOL
Class A: IFINX     Class B: ISHOX      Class C: AXFCX
Class I: AGMIX     Class R4: IDFYX     Class W: RSDWX
</Table>

(RIVERSOURCE INVESTMENTS LOGO)                               S-6042-99 AE (7/08)