Exhibit No.4 (a)(35)

                                     FORM OF
                    PREFERRED SECURITIES GUARANTEE AGREEMENT

                          Dated as of           , 1995
                                      ----------

This GUARANTEE AGREEMENT ("Guarantee Agreement"), dated as of _______, 1995, is
executed and delivered by Northwestern Public Service Company, a Delaware
corporation (the "Guarantor"), and Wilmington Trust Company, a Delaware banking
corporation, not in its individual capacity but solely as trustee (the
"Preferred Guarantee Trustee"), for the benefit of the Holders (as defined
herein) from time to time of the Preferred Securities (as defined herein) of
NWPS Capital Financing I, a Delaware statutory business trust (the "Issuer").

WHEREAS, pursuant to an Amended and Restated Declaration of Trust (the
"Declaration"), dated as of _________, 1995, among the trustees of the Issuer
named therein, the Guarantor as Sponsor and the holders from time to time of
undivided beneficial interests in the assets of the Issuer, the Issuer is
issuing on the date hereof $__________ aggregate stated liquidation amount of
Preferred Securities designated the ___% Trust Preferred Capital Securities (the
"Preferred Securities");

WHEREAS, as incentive for the Holders to purchase the Preferred Securities, the
Guarantor desires irrevocably and unconditionally to agree, to the extent set
forth in this Guarantee Agreement, to pay to the Holders of the Preferred
Securities the Guarantee Payments (as defined herein) and to make certain other
payments on the terms and conditions set forth herein;

WHEREAS, the Guarantor is also executing and delivering a guarantee agreement
(the "Common Securities Guarantee Agreement") in substantially identical terms
to this Guarantee Agreement for the benefit of the holders of the Common
Securities (as defined herein) except that if an Event of Default (as defined in
the Indenture (as defined herein)), has occurred and is continuing, the rights
of holders of the Common Securities to receive Guarantee Payments under the
Common Securities Guarantee are subordinated to the rights of Holders of
Preferred Securities to receive Guarantee Payments under this Guarantee
Agreement;

NOW, THEREFORE, in consideration of the purchase by each Holder of Preferred
Securities, which purchase the Guarantor hereby agrees shall benefit the
Guarantor, the Guarantor executes and delivers this Guarantee Agreement for the
benefit of the Holders.







                                    ARTICLE I
                         DEFINITIONS AND INTERPRETATION

SECTION 1.1.  Definitions and Interpretation.

In this Guarantee Agreement, unless the context otherwise requires:

      (a)   Capitalized terms used in this Guarantee Agreement but not defined
            in the preamble above have the respective meanings assigned to them
            in this Section 1.1 or in the Declaration as in effect on the date
            hereof;

      (b)   a term defined anywhere in this Guarantee Agreement has the same
            meaning throughout;

      (c)   all references to "the Guarantee Agreement" or "this Guarantee
            Agreement" are to this Guarantee Agreement as modified, supplemented
            or amended from time to time;

      (d)   all references in this Guarantee Agreement to Articles and Sections
            are to Articles and Sections of this Guarantee Agreement unless
            otherwise specified;

      (e)   a term defined in the Trust Indenture Act has the same meaning when
            used in this Guarantee Agreement unless otherwise defined in this
            Guarantee Agreement or unless the context otherwise requires; and

      (f)   a reference to the singular includes the plural and vice versa.

"Affiliate" has the same meaning as given to that term in Rule 405 promulgated
under the Securities Act of 1933, as amended, or any successor rule thereunder.

"Common Securities" means the securities representing common undivided
beneficial interests in the assets of the Issuer.

"Covered Person" means any Holder or beneficial owner of Preferred Securities.

"Event of Default" means a default by the Guarantor on any of its payment or
other obligations under this Guarantee Agreement.

"Guarantee Payments" means the following payments or distributions, without
duplication, with respect to the Preferred Securities, to the extent not paid or
made by the Issuer:  (i) any accrued and unpaid Distributions (as defined in the
Declaration) that are required to be paid on such Preferred Securities to the
extent the Issuer shall have funds legally available therefor, (ii) the
redemption price, including all accrued and unpaid Distributions to the date of
redemption (the "Redemption Price") to the extent the Issuer has funds


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available therefor, with respect to any Preferred Securities called for
redemption by the Issuer, and (iii) upon a voluntary or involuntary dissolution,
winding-up or termination of the Issuer (other than in connection with the
distribution of Debentures to the Holders in exchange for Preferred Securities
as provided in the Declaration or a redemption of all the Preferred Securities),
the lesser of (a) the aggregate of the liquidation amount and all accrued and
unpaid Distributions on the Preferred Securities to the date of payment to the
extent the Issuer has funds legally available therefor, and (b) the amount of
assets of the Issuer remaining available for distribution to Holders in
liquidation of the Issuer (in either case, the "Liquidation Distribution").  If
an event of default under the Indenture has occurred and is continuing, the
rights of holders of the Common Securities to receive payments under the Common
Securities Guarantee Agreement are subordinated to the rights of Holders of
Preferred Securities to receive Guarantee Payments.

"Holder" shall mean any holder, as registered on the books and records of the
Issuer of any Preferred Securities; provided, however, that, in determining
whether the holders of the requisite percentage of Preferred Securities have
given any request, notice, consent or waiver hereunder, "Holder" shall not
include the Guarantor or any Affiliate of the Guarantor.

"Indemnified Person" means the Preferred Guarantee Trustee, any Affiliate of the
Preferred Guarantee Trustee, or any officers, directors, shareholders, members,
partners, employees, representatives or agents of the Preferred Guarantee
Trustee.

"Indenture" means the Indenture dated as of __________, 1995, among the
Guarantor (the "Debenture Issuer") and _____________________________, as trustee
and any indenture supplemental thereto pursuant to which certain subordinated
debt securities of the Debenture Issuer are to be issued to the Property Trustee
of the Issuer.

"Majority in liquidation amount of the Securities" means, except as provided by
the Trust Indenture Act, a vote by Holder(s) of Preferred Securities, voting
separately as a class, of more than 50% of the liquidation amount (including the
stated amount that would be paid on redemption, liquidation or otherwise, plus
accrued and unpaid Distributions to the date upon which the voting percentages
are determined) of all Preferred Securities.

"Officers' Certificate" means, with respect to any Person, a certificate signed
by two Authorized Officers of such Person.  Any Officers' Certificate delivered
with respect to compliance with a condition or covenant provided for in this
Guarantee Agreement shall include:

      (a)   a statement that each officer signing the Officers' Certificate has
            read the covenant or condition and the definition relating thereto;



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      (b)   a brief statement of the nature and scope of the examination or
            investigation undertaken by each officer in rendering the Officers'
            Certificate;

      (c)   a statement that each such officer has made such examination or
            investigation as, in such officer's opinion, is necessary to enable
            such officer to express an informed opinion as to whether or not
            such covenant or condition has been complied with; and

      (d)   a statement as to whether, in the opinion of each such officer, such
            condition or covenant has been complied with.

"Person" means a legal person, including any individual, corporation, estate,
partnership, joint venture, association, joint stock company, limited liability
company, trust, unincorporated association, or government or any agency or
political subdivision thereof, or any other entity of whatever nature.

"Preferred Guarantee Trustee" means Wilmington Trust Company, in its capacity as
trustee hereunder and not in its individual capacity, until a Successor
Preferred Guarantee Trustee has been appointed and has accepted such appointment
pursuant to the terms of this Guarantee Agreement and thereafter means each such
Successor Preferred Guarantee Trustee.

"Responsible Officer" means, with respect to the Preferred Guarantee Trustee,
any vice-president, any assistant vice-president, the secretary, any assistant
secretary, the treasurer, any assistant treasurer, any trust officer or
assistant trust officer or any other officer of the Corporate Trust Department
of the Preferred Guarantee Trustee customarily performing functions similar to
those performed by any of the above designated officers and also means, with
respect to a particular corporate trust matter, any other officer to whom such
matter is referred because of that officer's knowledge of and familiarity with
the particular subject.

"Successor Preferred Guarantee Trustee" means a successor Preferred Guarantee
Trustee possessing the qualifications to act as Preferred Guarantee Trustee
under Section 4.1.

"Trust Indenture Act" means the Trust Indenture Act of 1939, as amended.


                                  ARTICLE II
                             TRUST INDENTURE ACT

SECTION 2.1.  Trust Indenture Act; Application.



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      (a)   This Guarantee Agreement is subject to the provisions of the Trust
            Indenture Act that are required to be part of this Guarantee
            Agreement and shall, to the extent applicable, be governed by such
            provisions; and

      (b)   if and to the extent that any provision of this Guarantee Agreement
            limits, qualifies or conflicts with the duties imposed by Section
            310 to 317, inclusive, of the Trust Indenture Act, such imposed
            duties shall control.

SECTION 2.2.  Lists of Holders of Securities.

      (a)   The Guarantor shall provide the Preferred Guarantee Trustee with a
            list, in such form as the Preferred Guarantee Trustee may reasonably
            require, of the name and addresses of the Holders of the Preferred
            Securities ("List of Holders") as of such date, (i) within 14 days
            after January 1 and June 30 of each year, and (ii) at any other time
            within 30 days of receipt by the Guarantor of a written request for
            a List of Holders as of a date no more than 14 days before such List
            of Holders is given to the Preferred Guarantee Trustee, provided
            that the Guarantor shall not be obligated to provide such List of
            Holders at any time the List of Holders does not differ from the
            most recent List of Holders given to the Preferred Guarantee Trustee
            by the Guarantor.  The Preferred Guarantee Trustee may destroy any
            List of Holders previously given to it on receipt of a new List of
            Holders.

      (b)   The Preferred Guarantee Trustee shall comply with its obligations
            under Section 311(a), 311(b) and Section 312(b) of the Trust
            Indenture Act.

SECTION 2.3.  Reports by the Preferred Guarantee Trustee.

Within 60 days after May 15 of each year, the Preferred Guarantee Trustee shall
provide to the Holders of the Preferred Securities such reports as are required
by Section 313 of the Trust Indenture Act, if any, in the form and in the manner
provided by Section 313 of the Trust Indenture Act.  The Preferred Guarantee
Trustee shall also comply with the requirements of Section 313(d) of the Trust
Indenture Act.

SECTION 2.4.  Periodic Reports to Preferred Guarantee Trustee.

The Guarantor shall provide to the Preferred Guarantee Trustee such documents,
reports and information as required by Section 314 (if any) and the compliance
certificate required by Section 314 of the Trust Indenture Act in the form, in
the manner and at the times required by Section 314 of the Trust Indenture Act.

SECTION 2.5.  Evidence of Compliance with Conditions Precedent.



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The Guarantor shall provide to the Preferred Guarantee Trustee such evidence of
compliance with any conditions precedent, if any, provided for in this Guarantee
Agreement that relate to any of the matters set forth in Section 314(c) of the
Trust Indenture Act.  Any certificate or opinion required to be given by an
officer pursuant to Section 314(c)(1) may be given in the form of an Officers'
Certificate.

SECTION 2.6.  Events of Default; Waiver.

The Holders of a Majority in liquidation amount of Preferred Securities may, by
vote, on behalf of the Holders of all of the Preferred Securities, waive any
past Event of Default and its consequences.  Upon such waiver, any such Event of
Default shall cease to exist, and any Event of Default arising therefrom shall
be deemed to have been cured, for every purpose of this Guarantee Agreement, but
no such waiver shall extend to any subsequent or other default or Event of
Default or impair any right consequent thereon.

SECTION 2.7.  Event of Default; Notice

      (a)   The Preferred Guarantee Trustee shall, within 90 days after the
            occurrence of an Event of Default, transmit by mail, first class
            postage prepaid, to the Holders of the Preferred Securities, notices
            of all Events of Default known to the Preferred Guarantee Trustee,
            unless such defaults have been cured before the giving of such
            notice, provided that the Preferred Guarantee Trustee shall be
            protected in withholding such notice if and so long as the board of
            directors, the executive committee, or a trust committee of
            directors and/or Responsible Officers of the Preferred Guarantee
            Trustee in good faith determines that the withholding of such notice
            is in the interests of the Holders of the Preferred Securities.

      (b)   The Preferred Guarantee Trustee shall not be deemed to have
            knowledge of any Event of Default unless the Preferred Guarantee
            Trustee shall have received written notice, or a Responsible Officer
            charged with the administration of the Declaration shall have
            obtained written notice, of such Event of Default.

SECTION 2.8   Conflicting Interests.

The Declaration shall be deemed to be specifically described in this Guarantee
Agreement for the purposes of clause (i) of the first proviso contained in
Section 310(b) of the Trust Indenture Act.


                                 ARTICLE III
                         POWERS, DUTIES AND RIGHTS OF
                         PREFERRED GUARANTEE TRUSTEE


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SECTION 3.1.  Powers and Duties of the Preferred Guarantee Trustee.

      (a)   This Guarantee Agreement shall be held by the Preferred Guarantee
            Trustee for the benefit of the Holders of the Preferred Securities,
            and the Preferred Guarantee Trustee shall not transfer this
            Guarantee Agreement to any Person except a Holder of Preferred
            Securities exercising his or her rights pursuant to Section 5.4(b)
            or to a Successor Preferred Guarantee Trustee on acceptance by such
            Successor Preferred Guarantee Trustee of its appointment to act as
            Successor Preferred Guarantee Trustee.  The right, title and
            interest of the Preferred Guarantee Trustee shall automatically vest
            in any Successor Preferred Guarantee Trustee, and such vesting and
            cessation of title shall be effective whether or not conveyancing
            documents have been executed and delivered pursuant to the
            appointment of such Successor Preferred Guarantee Trustee.

      (b)   If an Event of Default has occurred and is continuing, the Preferred
            Guarantee Trustee shall enforce this Guarantee Agreement for the
            benefit of the Holders of the Preferred Securities.

      (c)   The Preferred Guarantee Trustee, before the occurrence of any Event
            of Default and after the curing of all Events of Default that may
            have occurred, shall undertake to perform only such duties as are
            specifically set forth in this Guarantee Agreement, and no implied
            covenants shall be read into this Guarantee Agreement against the
            Preferred Guarantee Trustee.  In case an Event of Default has
            occurred (that has not been cured or waived pursuant to Section
            2.6), the Preferred Guarantee Trustee shall exercise such of the
            rights and powers vested in it by this Guarantee Agreement, and use
            the same degree of care and skill in its exercise thereof, as a
            prudent person would exercise or use under the circumstances in the
            conduct of his or her own affairs.

      (d)   No provision of this Guarantee Agreement shall be construed to
            relieve the Preferred Guarantee Trustee from liability for its own
            negligent action, its own negligent failure to act, or its own
            willful misconduct, except that:

            (i)   prior to the occurrence of any Event of Default and after the
                  curing or waiving of all such Events of Default that may have
                  occurred:

                  (a)   the duties and obligations of the Preferred Guarantee
                        Trustee shall be determined solely by the express
                        provisions of this Guarantee Agreement, and the
                        Preferred Guarantee Trustee shall not be liable except
                        for the performance of such duties and obligations as
                        are specifically set forth in this Guarantee Agreement,
                        and no implied covenants or obligations shall be


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                        read into this Guarantee Agreement against the Preferred
                        Guarantee Trustee; and

                  (b)   in the absence of bad faith on the part of the Preferred
                        Guarantee Trustee, the Preferred Guarantee Trustee may
                        conclusively rely, as to the truth of the statements and
                        the correctness of the opinions expressed therein, upon
                        any certificates or opinions furnished to the Preferred
                        Guarantee Trustee and conforming to the requirements of
                        this Guarantee Agreement; but in the case of any such
                        certificates or opinions that by any provision hereof
                        are specifically required to be furnished to the
                        Preferred Guarantee Trustee, the Preferred Guarantee
                        Trustee shall be under a duty to examine the same to
                        determine whether or not they conform to the
                        requirements of this Declaration;

            (ii)  the Preferred Guarantee Trustee shall not be liable for any
                  error of judgment made in good faith by a Responsible Officer
                  of the Preferred Guarantee Trustee, unless it shall be proved
                  that the Preferred Guarantee Trustee was negligent in
                  ascertaining the pertinent facts upon which such judgment was
                  made;

            (iii) the Preferred Guarantee Trustee shall not be liable with
                  respect to any action taken or omitted to be taken by it in
                  good faith in accordance with the direction of the Holders of
                  not less than a Majority in liquidation amount of the
                  Preferred Securities relating to the time, method and place of
                  conducting any proceeding for any remedy available to the
                  Preferred Guarantee Trustee, or exercising any trust or power
                  conferred upon the Preferred Guarantee Trustee under this
                  Guarantee Agreement; and

            (iv)  no provision of this Guarantee Agreement shall require the
                  Preferred Guarantee Trustee to expend or risk its own funds or
                  otherwise incur personal financial liability in the
                  performance of any of its duties or in the exercise of any of
                  its rights or powers, if the Preferred Guarantee Trustee shall
                  have reasonable grounds for believing that the repayment of
                  such funds or liability is not reasonably assured to it under
                  the terms of this Guarantee Agreement or adequate indemnity
                  such risk or liability is not reasonably assured to it.

SECTION 3.2.  Certain Rights of Preferred Guarantee Trustee.

      (a)   Subject to the provisions of Section 3.1:



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            (i)   the Preferred Guarantee Trustee may rely and shall be fully
                  protected in acting or refraining from acting upon any
                  resolution, certificate, statement, instrument, opinion,
                  report, notice, request, direction, consent, order, bond,
                  debenture, note, other evidence of indebtedness or other paper
                  or document believed by it to be genuine and to have been
                  signed, sent or presented by the proper party or parties;

            (ii)  any direction or act of the Guarantor contemplated by this
                  Guarantee Agreement shall be sufficiently evidenced by a
                  Direction or an Officers' Certificate;

            (iii) whenever, in the administration of this Guarantee Agreement,
                  the Preferred Guarantee Trustee shall deem it desirable that a
                  matter be proved or established before taking, suffering or
                  omitting any action hereunder, the Preferred Guarantee Trustee
                  (unless other evidence is herein specifically prescribed) may,
                  in the absence of bad faith on its part, request and rely upon
                  an Officers' Certificate which, upon receipt of such request,
                  shall be promptly delivered by the Guarantor;

            (iv)  the Preferred Guarantee Trustee shall have no duty to see to
                  any recording, filing or registration of any instrument (or
                  any rerecording, refiling or registration thereof);

            (v)   the Preferred Guarantee Trustee may consult with counsel, and
                  the written advice or opinion of such counsel with respect to
                  legal matters shall be full and complete authorization and
                  protection in respect of any action taken, suffered or omitted
                  by it hereunder in good faith and in accordance with such
                  advice or opinion.  Such counsel may be counsel to the
                  Guarantor or any of its Affiliates and may include any of its
                  employees.  The Preferred Guarantee Trustee shall have the
                  right at any time to seek instructions concerning the
                  administration of this Guarantee Agreement from any court of
                  competent jurisdiction;

            (vi)  the Preferred Guarantee Trustee shall be under no obligation
                  to exercise any of the rights or powers vested in it by this
                  Guarantee Agreement at the request or direction of any Holder,
                  unless such Holder shall have provided to the Preferred
                  Guarantee Trustee such adequate security and indemnity as
                  would satisfy a reasonable person in the position of the
                  Preferred Guarantee Trustee, against the costs, expenses
                  (including attorneys' fees and expenses) and liabilities that
                  might be incurred by it in complying with such request or
                  direction, including such reasonable advances as may be
                  requested by the Preferred Guarantee Trustee; provided that,
                  nothing contained in this Section 3.2(a)(vi) shall be taken to
                  relieve the Preferred Guarantee


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                  Trustee, upon the occurrence of an Event of Default, of its
                  obligation to exercise the rights and powers vested in it by
                  this Guarantee Agreement;

            (vii) the Preferred Guarantee Trustee shall not be bound to make any
                  investigation into the facts or matters stated in any
                  resolution, certificate, statement, instrument, opinion,
                  report, notice, request, direction, consent, order, bond,
                  debenture, note, other evidence of indebtedness or other paper
                  or document, but the Preferred Guarantee Trustee, in its
                  discretion, may make such further inquiry or investigation
                  into such facts or matters as it may see fit;

            (viii)the Preferred Guarantee Trustee may execute any of the trusts
                  or powers hereunder or perform any duties hereunder either
                  directly or by or through agents or attorneys, and the
                  Preferred Guarantee Trustee shall not be responsible for any
                  misconduct or negligence on the part of any agent or attorney
                  appointed with due care by it hereunder;

            (ix)  any action taken by the Preferred Guarantee Trustee or its
                  agents hereunder shall bind the Holders of the Preferred
                  Securities, and the signature of the Preferred Guarantee
                  Trustee or its agents alone shall be sufficient and effective
                  to perform any such action.  No third party shall be required
                  to inquire as to the authority of the Preferred Guarantee
                  Trustee to so act or as to its compliance with any of the
                  terms and provisions of this Guarantee Agreement, both of
                  which shall be conclusively evidenced by the Preferred
                  Guarantee Trustee's or its agent's taking such action; and

            (x)   whenever in the administration of this Guarantee Agreement the
                  Preferred Guarantee Trustee shall deem it desirable to receive
                  instructions with respect to enforcing any remedy or right or
                  taking any other action hereunder, the Preferred Guarantee
                  Trustee (i) may request instructions from the Holders of the
                  Preferred Securities, (ii) may refrain from enforcing such
                  remedy or right or taking such other action until such
                  instructions are received, and (iii) shall be protected in
                  acting in accordance with such instructions.

      (b)   No provision of this Guarantee Agreement shall be deemed to impose
            any duty or obligation on the Preferred Guarantee Trustee to perform
            any act or acts or exercise any right, power, duty or obligation
            conferred or imposed on it in any jurisdiction in which it shall be
            illegal, or in which the Preferred Guarantee Trustee shall be
            unqualified or incompetent in accordance with applicable law, to
            perform any such act or acts or to exercise any such right,


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            power, duty or obligation.  No permissive power or authority
            available to the Preferred Guarantee Trustee shall be construed to
            be a duty.



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SECTION 3.3.  Not Responsible for Recitals or Issuance of Guarantee.

The recitals contained in this Guarantee shall be taken as the statements of the
Guarantor, and the Preferred Guarantee Trustee does not assume any
responsibility for their correctness.  The Preferred Guarantee Trustee makes no
representation as to the validity or sufficiency of this Guarantee Agreement.


                                  ARTICLE IV
                         PREFERRED GUARANTEE TRUSTEE

SECTION 4.1.  Preferred Guarantee Trustee; Eligibility.

      (a)   There shall at all times be a Preferred Guarantee Trustee which
            shall:

            (i)   not be an Affiliate of the Guarantor; and

            (ii)  be a corporation organized and doing business under the laws
                  of the United States of America or any State or Territory
                  thereof or of the District of Columbia, or a corporation or
                  Person permitted by the Securities and Exchange Commission to
                  act as an institutional trustee under the Trust Indenture Act,
                  authorized under such laws to exercise corporate trust powers,
                  having a combined capital and surplus of at least 50 million
                  U.S. dollars ($50,000,000), and subject to supervision or
                  examination by Federal, State, Territorial or District of
                  Columbia authority.  If such corporation publishes reports of
                  condition at least annually, pursuant to law or to the
                  requirements of the supervising or examining authority
                  referred to above, then, for the purposes of this Section
                  4.1(a)(ii), the combined capital and surplus of such
                  corporation shall be deemed to be its combined capital and
                  surplus as set forth in its most recent report of condition so
                  published.

      (b)   If at any time the Preferred Guarantee Trustee shall cease to be
            eligible to so act under Section 4.1(a), the Preferred Guarantee
            Trustee shall immediately resign in the manner and with the effect
            set out in Section 4.2(c).

      (c)   If the Preferred Guarantee Trustee has or shall acquire any
            "conflicting interest" within the meaning of Section 310(b) of the
            Trust Indenture Act, the Preferred Guarantee Trustee and Guarantor
            shall in all respects comply with the provisions of Section 310(b)
            of the Trust Indenture Act.



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SECTION 4.2.  Appointment, Removal and Resignation of Preferred Guarantee
Trustees.

      (a)   Subject to Section 4.2(b), the Preferred Guarantee Trustee may be
            appointed or removed without cause at any time by the Guarantor.

      (b)   The Preferred Guarantee Trustee shall not be removed in accordance
            with Section 4.2(a) until a Successor Preferred Guarantee Trustee
            has been appointed and has accepted such appointment by written
            instrument executed by such Successor Preferred Guarantee Trustee
            and delivered to the Guarantor.

      (c)   The Preferred Guarantee Trustee appointed to office shall hold
            office until a Successor Preferred Guarantee Trustee shall have been
            appointed or until its removal or resignation.  The Preferred
            Guarantee Trustee may resign from office (without need for prior or
            subsequent accounting) by an instrument in writing executed by the
            Preferred Guarantee Trustee and delivered to the Guarantor, which
            resignation shall not take effect until a Successor Preferred
            Guarantee Trustee has been appointed and has accepted such
            appointment by instrument in writing executed by such Successor
            Preferred Guarantee Trustee and delivered to the Guarantor and the
            resigning Preferred Guarantee Trustee.

      (d)   If no Successor Preferred Guarantee Trustee shall have been
            appointed and accepted appointment as provided in this Section 4.2
            within 60 days after delivery to the Guarantor of an instrument of
            resignation, the resigning Preferred Guarantee Trustee may petition
            a court of competent jurisdiction for appointment of a Successor
            Preferred Guarantee Trustee.  Such court may thereupon, after
            prescribing such notice, if any, as it may deem proper, appoint a
            Successor Preferred Guarantee Trustee.


                                  ARTICLE V
                                  GUARANTEE

SECTION 5.1.  Guarantee.

The Guarantor irrevocably and unconditionally agrees to pay in full to the
Holders the Guarantee Payments (without duplication of amounts theretofore paid
by the Issuer), as and when due, regardless of any defense, right of set-off or
counterclaim that the Issuer may have or assert.  The Guarantor's obligation to
make a Guarantee Payment may be satisfied by direct payment of the required
amounts by the Guarantor to the Holders or by causing the Issuer to pay such
amounts to the Holders.



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SECTION 5.2.  Waiver of Notice and Demand.

The Guarantor hereby waives notice of acceptance of this Guarantee Agreement and
of any liability to which it applies or may apply, presentment, demand for
payment, any right to require a proceeding first against the Issuer or any other
Person before proceeding against the Guarantor, protest, notice of nonpayment,
notice of dishonor, notice of redemption and all other notices and demands.

SECTION 5.3.  Obligations Not Affected

The obligations, covenants, agreements and duties of the Guarantor under this
Guarantee Agreement shall in no way be affected or impaired by reason of the
happening from time to time of any of the following:

      (a)   the release or waiver, by operation of law or otherwise, of the
            performance or observance by the Issuer of any express or implied
            agreement, covenant, term or condition relating to the Preferred
            Securities to be performed or observed by the Issuer;

      (b)   the extension of time for the payment by the Issuer of all or any
            portion of the Distributions, Redemption Price, Liquidation
            Distribution or any other sums payable under the terms of the
            Preferred Securities or the extension of time for the performance of
            any other obligation under, arising out of, or in connection with,
            the Preferred Securities (other than an extension of time for
            payment of Distributions, Redemption Price, Liquidation Distribution
            or other sum payable that results from the extension of any interest
            payment period on the Debentures or any extension of the maturity
            date of the Debentures permitted by the Indenture);

      (c)   any failure, omission, delay or lack of diligence on the part of the
            Holders to enforce, assert or exercise any right, privilege, power
            or remedy conferred on the Holders pursuant to the terms of the
            Preferred Securities, or any action on the part of the Issuer
            granting indulgence or extension of any kind;

      (d)   the voluntary or involuntary liquidation, dissolution, sale of any
            collateral, receivership, insolvency, bankruptcy, assignment for the
            benefit of creditors, reorganization, arrangement, composition or
            readjustment of debt of, or other similar proceedings affecting, the
            Issuer or any of the assets of the Issuer;

      (e)   any invalidity of, or defect or deficiency in the Preferred
            Securities;

      (f)   the settlement or compromise of any obligation guaranteed hereby or
            hereby incurred; or



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      (g)   any other circumstance whatsoever that might otherwise constitute a
            legal or equitable discharge or defense of a guarantor, it being the
            intent of this Section 5.3 that the obligations of the Guarantor
            hereunder shall be absolute and unconditional under any and all
            circumstances.  There shall be no obligation of the Holders to give
            notice to, or obtain consent of, the Guarantor with respect to the
            happening of any of the foregoing.

SECTION 5.4.  Rights of Holders.

      (a)   The Holders of a Majority in liquidation amount of the Preferred
            Securities have the right to direct the time, method and place of
            conducting any proceeding for any remedy available to the Preferred
            Guarantee Trustee in respect of this Guarantee Agreement or
            exercising any trust or power conferred upon the Preferred Guarantee
            Trustee under this Guarantee Agreement.

      (b)   If the Preferred Guarantee Trustee fails to enforce this Guarantee
            Agreement, any Holder of Preferred Securities may, after a period of
            30 days has elapsed from such Holder's written request to the
            Preferred Guarantee Trustee to enforce this Guarantee Agreement,
            institute a legal proceeding directly against the Guarantor to
            enforce its rights under this Guarantee Agreement, without first
            instituting a legal proceeding against the Issuer, the Preferred
            Guarantee Trustee or any other Person.

SECTION 5.5.  Guarantee of Payment.

This Guarantee Agreement creates a guarantee of payment and not of collection.
The Guarantor agrees that this Guarantee Agreement shall not be discharged
except by payment of the Guarantee Payments in full and by complete performance
of all obligations of the Guarantor contained in this Guarantee Agreement.

SECTION 5.6.  Subrogation.

The Guarantor shall be subrogated to all (if any) rights of the  Holders of
Preferred Securities against the Issuer in respect of any amounts paid to such
Holders by the Guarantor under this Guarantee Agreement; provided, however, that
the Guarantor shall not (except to the extent required by mandatory provisions
of law) be entitled to enforce or exercise any right that it may acquire by way
of subrogation or any indemnity, reimbursement or other agreement, in all cases
as a result of payment under this Guarantee Agreement, if, at the time of any
such payment, any amounts are due and unpaid under this Guarantee Agreement.  If
any amount shall be paid to the Guarantor in violation of the preceding
sentence, the Guarantor agrees to hold such amount in trust for the Holders and
to pay over such amount to the Holders.



                                     -15-




SECTION 5.7.  Independent Obligations.

The Guarantor acknowledges that its obligations hereunder are independent of the
obligations of the Issuer with respect to the Preferred Securities, and that the
Guarantor shall be liable as principal and as debtor hereunder to make Guarantee
Payments pursuant to the terms of this Guarantee Agreement notwithstanding the
occurrence of any event referred to in subsections (a) through (g), inclusive,
of Section 5.3 hereof.


                                  ARTICLE VI
                  LIMITATION OF TRANSACTIONS; SUBORDINATION

SECTION 6.1.  Limitation of Transactions.

So long as any Preferred Securities remain outstanding, if there shall have
occurred an Event of Default, or an Event of Default under the Declaration, or
if the Guarantor has given notice of its selection of an Extension Period (as
defined in the Indenture) and such period or any extension thereof, is
continuing, then, in each case, (a) the Guarantor shall not declare or pay any
dividend on, or make any distribution with respect to, or redeem, purchase,
acquire or make any distribution with respect to, any of its capital stock and
(b) the Guarantor shall not make any payment of interest, principal or premium,
if any, on or repay, repurchase or redeem any debt securities issued by the
Guarantor which rank pari passu with or junior to the Debentures; provided that
the foregoing restriction in this Section 6.1 (a) shall not apply to any stock
dividends paid by the Guarantor where the dividend stock is the same stock as
that on which the dividend is being paid.

SECTION 6.2.  Ranking.

This Guarantee Agreement will constitute an unsecured obligation of the
Guarantor and will rank (i) subordinate and junior in right of payment to all
other liabilities of the Guarantor, (ii) pari passu with the most senior
preferred or preference stock now or hereafter issued by the Guarantor and with
any guarantee now or hereafter entered into by the Guarantor in respect of any
preferred or preference stock of any Affiliate of the Guarantor, and (iii)
senior to the Guarantor's common stock.

                                 ARTICLE VII
                                 TERMINATION

SECTION 7.1.  Termination.

This Guarantee Agreement shall terminate upon (i) full payment of the Redemption
Price of all Securities, (ii) upon the distribution of the Debentures to the
Holders of all of the Preferred Securities or (iii) upon full payment of the
amounts payable in accordance with the Declaration upon liquidation of the
Issuer. Notwithstanding the foregoing, this


                                     -16-




Guarantee Agreement will continue to be effective or will be reinstated, as the
case may be, if at any time any Holder of Preferred Securities must restore
payment of any sums paid under the Preferred Securities or under this Preferred
Securities Guarantee.


                                 ARTICLE VIII
                               INDEMNIFICATION

SECTION 8.1.  Exculpation.

      (a)   No Indemnified Person shall be liable, responsible or accountable in
            damages or otherwise to the Guarantor or any Covered Person for any
            loss, damage or claim incurred by reason of any act or omission
            performed or omitted by such Indemnified Person in good faith in
            accordance with this Guarantee Agreement and in a manner that such
            Indemnified Person reasonably believed to be within the scope of the
            authority conferred on such Indemnified Person by this Guarantee
            Agreement or by law, except that an Indemnified Person shall be
            liable for any such loss, damage or claim incurred by reason of such
            Indemnified Person's negligence or willful misconduct with respect
            to such acts or  omissions.

      (b)   An Indemnified Person shall be fully protected in relying in good
            faith upon the records of the Guarantor and upon such information,
            opinions, reports or statements presented to the Guarantor by any
            Person as to matters the Indemnified Person reasonably believes are
            within such other Person's professional or expert competence and who
            has been selected with reasonable care by or on behalf of the
            Guarantor, including information, opinions, reports or statements as
            to the value and amount of the assets, liabilities, profits, losses,
            or any other facts pertinent to the existence and amount of assets
            from which Distributions to Holders of Preferred Securities might
            properly be paid.

SECTION 8.2.  Indemnification.

      (a)   To the fullest extent permitted by applicable law, the Guarantor
            shall indemnify and hold harmless each Indemnified Person from and
            against any loss, damage or claim incurred by such Indemnified
            Person by reason of any act or omission performed or omitted by such
            Indemnified Person in good faith in accordance with this Guarantee
            Agreement and in a manner such Indemnified Person reasonably
            believed to be within the scope of authority conferred on such
            Indemnified Person by this in accordance with this Guarantee
            Agreement, except that no Indemnified Person shall be entitled to be
            indemnified in respect of any loss, damage or claim incurred by such
            Indemnified Person by reason of negligence or willful misconduct
            with respect to such acts or omissions.


                                     -17-




      (b)   To the fullest extent permitted by applicable law, expenses
            (including legal fees) incurred by an Indemnified Person in
            defending any claim, demand, action, suit or proceeding shall, from
            time to time, be advanced by the Guarantor prior to the final
            disposition of such claim, demand, action, suit or proceeding upon
            receipt by the Guarantor of an undertaking by or on behalf of the
            Indemnified Person to repay such amount if it shall be determined
            that the Indemnified Person is not entitled to be indemnified as
            authorized in Section 8.2(a).

                                  ARTICLE IX
                                MISCELLANEOUS

SECTION 9.1.  Successors and Assigns.

All guarantees and agreements contained in this Guarantee Agreement shall bind
the successors, assigns, receivers, trustees and representatives of the
Guarantor and shall inure to the benefit of the Holders of the Preferred
Securities then outstanding.

SECTION 9.2.  Amendments.

Except with respect to any changes that do not materially adversely affect the
rights of Holders (in which case no consent of Holders will be required), this
Guarantee Agreement may only be amended with the prior approval of the Holders
of at least 66-2/3% in liquidation amount (including the stated amount that
would be paid on redemption, liquidation or otherwise, plus accrued and unpaid
Distributions to the date upon which the voting percentages are determined) of
all the outstanding Preferred Securities. The provisions of Section 12.2 of the
Declaration with respect to meetings of Holders of the Securities apply to the
giving of such approval.

SECTION 9.3.  Notices.

All notices provided for in this Guarantee Agreement shall be in writing, duly
signed by the party giving such notice, and shall be delivered, telecopied or
mailed by registered or certified mail, as follows:

      (a)   If given to the Preferred Guarantee Trustee, at the Preferred
            Guarantee Trustee's mailing address set forth below (or such other
            address as the Preferred Guarantee Trustee may give notice of to the
            Holders of the Preferred Securities):

                  Wilmington Trust Company
                  Rodney Square North
                  1100 N. Market Street
                  Wilmington, Delaware  19890-0001
                  Attn: Corporate Trust Administration


                                     -18-




      (b)   If given to the Guarantor, at the Guarantor's mailing address set
            forth below (or such other address as the Guarantor may give notice
            of to the Holders of the Preferred Securities):

                  Northwestern Public Service Company
                  33 Third Street, S.E.
                  Huron, South Dakota  57350

      (c)   If given to any Holder of Preferred Securities, at the address set
            forth on the books and records of the Issuer.

All such notices shall be deemed to have been given when received  in person,
telecopied with receipt confirmed, or mailed by first class mail, postage
prepaid except that if a notice or other document is refused delivery or cannot
be delivered because of a changed address of which no notice was given, such
notice or other document shall be deemed to have been delivered on the date of
such refusal or inability to deliver.

SECTION 9.4.  Benefit.

This Guarantee Agreement is solely for the benefit of the Holders of the
Preferred Securities and the Preferred Guarantee Trustee and, subject to Section
3.1(a), is not separately transferable from the Preferred Securities.

SECTION 9.5.  Governing Law.

THIS GUARANTEE AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED AND INTERPRETED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

THIS GUARANTEE AGREEMENT is executed as of the day and year first above written.

                                          Northwestern Public Service Company


                                          By:
                                             -------------------------------
                                                Name:
                                                Title:

                                          Wilmington Trust Company,
                                          as Preferred Guarantee Trustee


                                          By:
                                             -------------------------------
                                                Name:
                                                Title:

CHI2:1628.1 06.19.95 21.17

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