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                                   BY-LAWS

                                      OF

                          MORGAN STANLEY DEAN WITTER
                     MUNICIPAL INCOME OPPORTUNITIES TRUST

                    AMENDED AND RESTATED AS OF MAY 1, 1999

                                  ARTICLE I
                                 DEFINITIONS

   The terms "Commission," "Declaration," "Distributor," "Investment
Adviser," "Majority Shareholder Vote," "1940 Act," "Shareholder," "Shares,"
"Transfer Agent," "Trust," "Trust Property," and "Trustees" have the
respective meanings given them in the Declaration of Trust of Morgan Stanley
Dean Witter Municipal Income Opportunities Trust dated June 22, 1988, as
amended from time to time.

                                  ARTICLE II
                                   OFFICES

   SECTION 2.1. Principal Office. Until changed by the Trustees, the
principal office of the Trust in the Commonwealth of Massachusetts shall be
in the City of Boston, County of Suffolk.

   SECTION 2.2. Other Offices. In addition to its principal office in the
Commonwealth of Massachusetts, the Trust may have an office or offices in the
City of New York, State of New York, and at such other places within and
without the Commonwealth as the Trustees may from time to time designate or
the business of the Trust may require.

                                 ARTICLE III
                            SHAREHOLDERS' MEETINGS

   SECTION 3.1. Place of Meetings. Meetings of Shareholders shall be held at
such place, within or without the Commonwealth of Massachusetts, as may be
designated from time to time by the Trustees.

   SECTION 3.2. Annual Meetings. An annual meeting of Shareholders, at which
the Shareholders shall elect Trustees and transact such other business as may
properly come before the meeting, shall be held, commencing in 1989, in
December of each year, the precise date during December to be fixed by the
Board of Trustees.

   SECTION 3.3. Special Meetings. Special meetings of Shareholders of the
Trust shall be held whenever called by the Board of Trustees or the President
of the Trust. Special meetings of Shareholders shall also be called by the
Secretary upon the written request of the holders of Shares entitled to vote
not less than twenty-five percent (25%) of all the votes entitled to be cast
at such meeting. Such request shall state the purpose or purposes of such
meeting and the matters proposed to be acted on thereat. The Secretary shall
inform such Shareholders of the reasonable estimated cost of preparing and
mailing such notice of the meeting, and, upon payment to the Trust of such
costs, the Secretary shall give notice stating the purpose or purposes of the
meeting to all entitled to vote at such meeting. No special meeting need be
called upon the request of the holders of Shares entitled to cast less than a
majority of all votes entitled to be cast at such meeting, to consider any
matter which is substantially the same as a matter voted upon at any special
meeting of Shareholders held during the preceding twelve months.

   SECTION 3.4. Notice of Meetings. Written or printed notice of every
Shareholders' meeting stating the place, date, and purpose or purposes
thereof, shall be given by the Secretary not less than ten (10) nor more than
ninety (90) days before such meeting to each Shareholder entitled to vote at
such meeting. Such notice shall be deemed to be given when deposited in the
United States mail, postage prepaid, directed to the Shareholder at his
address as it appears on the records of the Trust.

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   SECTION 3.5. Quorum and Adjournment of Meetings. Except as otherwise
provided by law, by the Declaration or by these By-Laws, at all meetings of
Shareholders, the holders of a majority of the Shares issued and outstanding
and entitled to vote thereat, present in person or represented by proxy,
shall be requisite and shall constitute a quorum for the transaction of
business. In the absence of a quorum, the Shareholders present or represented
by proxy and entitled to vote thereat shall have the power to adjourn the
meeting from time to time. The Shareholders present in person or represented
by proxy at any meeting and entitled to vote thereat also shall have the
power to adjourn the meeting from time to time if the vote required to
approve or reject any proposal described in the original notice of such
meeting is not obtained (with proxies being voted for or against adjournment
consistent with the votes for and against the proposal for which the required
vote has not been obtained). The affirmative vote of the holders of a
majority of the Shares then present in person or represented by proxy shall
be required to adjourn any meeting. Any adjourned meeting may be reconvened
without further notice or change in record date. At any reconvened meeting at
which a quorum shall be present, any business may be transacted that might
have been transacted at the meeting as originally called.

   SECTION 3.6. Voting Rights, Proxies.  At each meeting of Shareholders,
each holder of record of Shares entitled to vote thereat shall be entitled to
one vote in person or by proxy for each Share of beneficial interest of the
Trust and for the fractional portion of one vote for each fractional Share
entitled to vote so registered in his or her name on the records of the Trust
on the date fixed as the record date for the determination of Shareholders
entitled to vote at such meeting. Without limiting the manner in which a
Shareholder may authorize another person or persons to act for such
Shareholder as proxy pursuant hereto, the following shall constitute a valid
means by which a Shareholder may grant such authority:

       (i) A Shareholder may execute a writing authorizing another person or
       persons to act for such Shareholder as proxy. Execution may be
       accomplished by the Shareholder or such Shareholder's authorized
       officer, director, employee, attorney-in-fact or another agent signing
       such writing or causing such person's signature to be affixed to such
       writing by any reasonable means including, but not limited to, by
       facsimile or telecopy signature. No written evidence of authority of a
       Shareholder's authorized officer, director, employee, attorney-in-fact
       or other agent shall be required; and

       (ii) A Shareholder may authorize another person or persons to act for
       such Shareholder as proxy by transmitting or authorizing the
       transmission of a telegram or cablegram or by other means of
       telephonic, electronic or computer transmission to the person who will
       be the holder of the proxy or to a proxy solicitation firm, proxy
       support service organization or like agent duly authorized by the
       person who will be the holder of the proxy to receive such
       transmission, provided that any such telegram or cablegram or other
       means of telephonic, electronic or computer transmission must either
       set forth or be submitted with information from which it can be
       determined that the telegram, cablegram or other transmission was
       authorized by the Shareholder.

No proxy shall be valid after eleven months from its date, unless otherwise
provided in the proxy. At all meetings of Shareholders, unless the voting is
conducted by inspectors, all questions relating to the qualification of
voters and the validity of proxies and the acceptance or rejection of votes
shall be decided by the chairman of the meeting. In determining whether a
telegram, cablegram or other electronic transmission is valid, the chairman
or inspector, as the case may be, shall specify the information upon which he
or she relied. Pursuant to a resolution of a majority of the Trustees,
proxies may be solicited in the name of one or more Trustees or Officers of
the Trust. Proxy solicitations may be made in writing or by using telephonic
or other electronic solicitation procedures that include appropriate methods
of verifying the identity of the Shareholder and confirming any instructions
given thereby.

   SECTION 3.7. Vote Required. Except as otherwise provided by law, by the
Declaration of Trust, or by these By-Laws, at each meeting of Shareholders at
which a quorum is present, all matters shall be decided by Majority
Shareholder Vote.

   SECTION 3.8. Inspectors of Election. In advance of any meeting of
Shareholders, the Trustees may appoint Inspectors of Election to act at the
meeting or any adjournment thereof. If Inspectors of Election are not so
appointed, the chairman of any meeting of Shareholders may, and on the
request of any Shareholder or his proxy shall, appoint Inspectors of Election
of the meeting. In case any person appointed as Inspector fails to appear or
fails or refuses to act, the vacancy may be filled by appointment

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made by the Trustees in advance of the convening of the meeting or at the
meeting by the person acting as chairman. The Inspectors of Election shall
determine the number of Shares outstanding, the Shares represented at the
meeting, the existence of a quorum, the authenticity, validity and effect of
proxies, shall receive votes, ballots or consents, shall hear and determine
all challenges and questions in any way arising in connection with the right
to vote, shall count and tabulate all votes or consents, determine the
results, and do such other acts as may be proper to conduct the election or
vote with fairness to all Shareholders. On request of the chairman of the
meeting, or of any Shareholder or his proxy, the Inspectors of Election shall
make a report in writing of any challenge or question or matter determined by
them and shall execute a certificate of any facts found by them.

   SECTION 3.9. Inspection of Books and Records. Shareholders shall have such
rights and procedures of inspection of the books and records of the Trust as
are granted to Shareholders under Section 32 of the Business Corporation Law
of the Commonwealth of Massachusetts.

   SECTION 3.10. Action by Shareholders Without Meeting. Except as otherwise
provided by law, the provisions of these By-Laws relating to notices and
meetings to the contrary notwithstanding, any action required or permitted to
be taken at any meeting of Shareholders may be taken without a meeting if a
majority of the Shareholders entitled to vote upon the action consent to the
action in writing and such consents are filed with the records of the Trust.
Such consent shall be treated for all purposes as a vote taken at a meeting
of Shareholders.

   SECTION 3.11. Presence at Meetings. Presence at meetings of shareholders
requires physical attendance by the shareholder or his or her proxy at the
meeting site and does not encompass attendance by telephonic or other
electronic means.

                                  ARTICLE IV
                                   TRUSTEES

   SECTION 4.1. Meetings of the Trustees. The Trustees may in their
discretion provide for regular or special meetings of the Trustees. Regular
meetings of the Trustees may be held at such time and place as shall be
determined from time to time by the Trustees without further notice. Special
meetings of the Trustees may be called at any time by the President and shall
be called by the President or the Secretary upon the written request of any
two (2) Trustees.

   SECTION 4.2. Notice of Special Meetings. Written notice of special
meetings of the Trustees, stating the place, date and time thereof, shall be
given not less than two (2) days before such meeting to each Trustee,
personally, by telegram, by mail, or by leaving such notice at his place of
residence or usual place of business. If mailed, such notice shall be deemed
to be given when deposited in the United States mail, postage prepaid,
directed to the Trustee at his address as it appears on the records of the
Trust. Subject to the provisions of the 1940 Act, notice or waiver of notice
need not specify the purpose of any special meeting.

   SECTION 4.3. Telephone Meetings. Subject to the provisions of the 1940
Act, any Trustee, or any member or members of any committee designated by the
Trustees, may participate in a meeting of the Trustees, or any such
committee, as the case may be, by means of a conference telephone or similar
communications equipment if all persons participating in the meeting can hear
each other at the same time. Participation in a meeting by these means
constitutes presence in person at the meeting.

   SECTION 4.4. Quorum, Voting and Adjournment of Meetings. At all meetings
of the Trustees, a majority of the Trustees shall be requisite to and shall
constitute a quorum for the transaction of business. If a quorum is present,
the affirmative vote of a majority of the Trustees present shall be the act
of the Trustees, unless the concurrence of a greater proportion is expressly
required for such action by law, the Declaration or these By-Laws. If at any
meeting of the Trustees there be less than a quorum present, the Trustees
present thereat may adjourn the meeting from time to time, without notice
other than announcement at the meeting, until a quorum shall have been
obtained.

   SECTION 4.5. Action by Trustees Without Meeting. The provisions of these
By-Laws covering notices and meetings to the contrary notwithstanding, and
except as required by law, any action required

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or permitted to be taken at any meeting of the Trustees may be taken without
a meeting if a consent in writing setting forth the action shall be signed by
all of the Trustees entitled to vote upon the action and such written consent
is filed with the minutes of proceedings of the Trustees.

   SECTION 4.6. Expenses and Fees. Each Trustee may be allowed expenses, if
any, for attendance at each regular or special meeting of the Trustees, and
each Trustee who is not an officer or employee of the Trust or of its
investment manager or underwriter or of any corporate affiliate of any of
said persons shall receive for services rendered as a Trustee of the Trust
such compensation as may be fixed by the Trustees. Nothing herein contained
shall be construed to preclude any Trustee from serving the Trust in any
other capacity and receiving compensation therefor.

   SECTION 4.7. Execution of Instruments and Documents and Signing of Checks
and Other Obligations and Transfers. All instruments, documents and other
papers shall be executed in the name and on behalf of the Trust and all
checks, notes, drafts and other obligations for the payment of money by the
Trust shall be signed, and all transfer of securities standing in the name of
the Trust shall be executed, by the Chairman, the President, any Vice
President or the Treasurer or by any one or more officers or agents of the
Trust as shall be designated for that purpose by vote of the Trustees;
notwithstanding the above, nothing in this Section 4.7 shall be deemed to
preclude the electronic authorization, by designated persons, of the Trust's
Custodian (as described herein in Section 9.1) to transfer assets of the
Trust, as provided for herein in Section 9.1.

   SECTION 4.8. Indemnification of Trustees, Officers, Employees and
Agents. (a) The Trust shall indemnify any person who was or is a party or is
threatened to be made a party to any threatened, pending, or completed
action, suit or proceeding, whether civil, criminal, administrative or
investigative (other than an action by or in the right of the Trust) by
reason of the fact that he is or was a Trustee, officer, employee, or agent
of the Trust. The indemnification shall be against expenses, including
attorneys' fees, judgments, fines, and amounts paid in settlement, actually
and reasonably incurred by him in connection with the action, suit, or
proceeding, if he acted in good faith and in a manner he reasonably believed
to be in or not opposed to the best interests of the Trust, and, with respect
to any criminal action or proceeding, had no reasonable cause to believe his
conduct was unlawful. The termination of any action, suit or proceeding by
judgment, order, settlement, conviction, or upon a plea of nolo contendere or
its equivalent, shall not, of itself, create a presumption that the person
did not act in good faith and in a manner which he reasonably believed to be
in or not opposed to the best interests of the Trust, and, with respect to
any criminal action or proceeding, had reasonable cause to believe that his
conduct was unlawful.

   (b) The Trust shall indemnify any person who was or is a party or is
threatened to be made a party to any threatened, pending or completed action
or suit by or on behalf of the Trust to obtain a judgment or decree in its
favor by reason of the fact that he is or was a Trustee, officer, employee,
or agent of the Trust. The indemnification shall be against expenses,
including attorneys' fees actually and reasonably incurred by him in
connection with the defense or settlement of the action or suit, if he acted
in good faith and in a manner he reasonably believed to be in or not opposed
to the best interests of the Trust; except that no indemnification shall be
made in respect of any claim, issue, or matter as to which the person has
been adjudged to be liable for negligence or misconduct in the performance of
his duty to the Trust, except to the extent that the court in which the
action or suit was brought, or a court of equity in the county in which the
Trust has its principal office, determines upon application that, despite the
adjudication of liability but in view of all circumstances of the case, the
person is fairly and reasonably entitled to indemnity for those expenses
which the court shall deem proper, provided such Trustee, officer, employee
or agent is not adjudged to be liable by reason of his willful misfeasance,
bad faith, gross negligence or reckless disregard of the duties involved in
the conduct of his office.

   (c) To the extent that a Trustee, officer, employee, or agent of the Trust
has been successful on the merits or otherwise in defense of any action, suit
or proceeding referred to in subsection (a) or (b) or in defense of any
claim, issue or matter therein, he shall be indemnified against expenses,
including attorneys' fees, actually and reasonably incurred by him in
connection therewith.

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   (d) (1) Unless a court orders otherwise, any indemnification under
subsections (a) or (b) of this section may be made by the Trust only as
authorized in the specific case after a determination that indemnification of
the Trustee, officer, employee, or agent is proper in the circumstances
because he has met the applicable standard of conduct set forth in
subsections (a) or (b).

       (2) The determination shall be made:

       (i) By the Trustees, by a majority vote of a quorum which consists of
    Trustees who were not parties to the action, suit or proceeding; or

      (ii) If the required quorum is not obtainable, or if a quorum of
    disinterested Trustees so directs, by independent legal counsel in a
    written opinion; or

     (iii) By the Shareholders.

     (3) Notwithstanding any provision of this Section 4.8, no person shall
    be entitled to indemnification for any liability, whether or not there is
    an adjudication of liability, arising by reason of willful misfeasance,
    bad faith, gross negligence, or reckless disregard of duties as described
    in Section 17(h) and (i) of the Investment Company Act of 1940
    ("disabling conduct"). A person shall be deemed not liable by reason of
    disabling conduct if, either:

       (i) a final decision on the merits is made by a court or other body
    before whom the proceeding was brought that the person to be indemnified
    ("indemnitee") was not liable by reason of disabling conduct; or

     (ii) in the absence of such a decision, a reasonable determination,
    based upon a review of the facts, that the indemnitee was not liable by
    reason of disabling conduct, is made by either--

          (A) a majority of a quorum of Trustees who are neither "interested
         persons" of the Trust, as defined in Section 2(a)(19) of the
         Investment Company Act of 1940, nor parties to the action, suit or
         proceeding, or

          (B) an independent legal counsel in a written opinion.

   (e) Expenses, including attorneys' fees, incurred by a Trustee, officer,
employee or agent of the Trust in defending a civil or criminal action, suit
or proceeding may be paid by the Trust in advance of the final disposition
thereof if:

       (1) authorized in the specific case by the Trustees; and

    (2) the Trust receives an undertaking by or on behalf of the Trustee,
   officer, employee or agent of the Trust to repay the advance if it is not
   ultimately determined that such person is entitled to be indemnified by
   the Trust; and

       (3) either, (i) such person provides a security for his undertaking,
or

      (ii) the Trust is insured against losses by reason of any lawful
    advances, or

     (iii) a determination, based on a review of readily available facts,
    that there is reason to believe that such person ultimately will be found
    entitled to indemnification, is made by either--

          (A) a majority of a quorum which consists of Trustees who are
         neither "interested persons" of the Trust, as defined in Section
         2(a)(19) of the 1940 Act, nor parties to the action, suit or
         proceeding, or

          (B) an independent legal counsel in a written opinion.

   (f) The indemnification provided by this Section shall not be deemed
exclusive of any other rights to which a person may be entitled under any
by-law, agreement, vote of Shareholders or disinterested Trustees or
otherwise, both as to action in his official capacity and as to action in
another capacity while holding the office, and shall continue as to a person
who has ceased to be a Trustee, officer, employee, or agent and inure to the
benefit of the heirs, executors and administrators of such person; provided
that no

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person may satisfy any right of indemnity or reimbursement granted herein or
to which he may be otherwise entitled except out of the property of the
Trust, and no Shareholder shall be personally liable with respect to any
claim for indemnity or reimbursement or otherwise.

   (g) The Trust may purchase and maintain insurance on behalf of any person
who is or was a Trustee, officer, employee, or agent of the Trust, against
any liability asserted against him and incurred by him in any such capacity,
or arising out of his status as such. However, in no event will the Trust
purchase insurance to indemnify any officer or Trustee against liability for
any act for which the Trust itself is not permitted to indemnify him.

   (h) Nothing contained in this Section shall be construed to protect any
Trustee or officer of the Trust against any liability to the Trust or to its
security holders to which he would otherwise be subject by reason of willful
misfeasance, bad faith, gross negligence or reckless disregard of the duties
involved in the conduct of his office.

                                  ARTICLE V
                                  COMMITTEES

   SECTION 5.1. Executive and Other Committees. The Trustees, by resolution
adopted by a majority of the Trustees, may designate an Executive Committee
and/or committees, each committee to consist of two (2) or more of the
Trustees of the Trust and may delegate to such committees, in the intervals
between meetings of the Trustees, any or all of the powers of the Trustees in
the management of the business and affairs of the Trust. In the absence of
any member of any such committee, the members thereof present at any meeting,
whether or not they constitute a quorum, may appoint a Trustee to act in
place of such absent member. Each such committee shall keep a record of its
proceedings.

   The Executive Committee and any other committee shall fix its own rules or
procedure, but the presence of at least fifty percent (50%) of the members of
the whole committee shall in each case be necessary to constitute a quorum of
the committee and the affirmative vote of the majority of the members of the
committee present at the meeting shall be necessary to take action.

   All actions of the Executive Committee shall be reported to the Trustees
at the meeting thereof next succeeding to the taking of such action.

   SECTION 5.2. Advisory Committee. The Trustees may appoint an advisory
committee which shall be composed of persons who do not serve the Trust in
any other capacity and which shall have advisory functions with respect to
the investments of the Trust but which shall have no power to determine that
any security or other investment shall be purchased, sold or otherwise
disposed of by the Trust. The number of persons constituting any such
advisory committee shall be determined from time to time by the Trustees. The
members of any such advisory committee may receive compensation for their
services and may be allowed such fees and expenses for the attendance at
meetings as the Trustees may from time to time determine to be appropriate.

   SECTION 5.3. Committee Action Without Meeting. The provisions of these
By-Laws covering notices and meetings to the contrary notwithstanding, and
except as required by law, any action required or permitted to be taken at
any meeting of any Committee of the Trustees appointed pursuant to Section
5.1 of these By-Laws may be taken without a meeting if a consent in writing
setting forth the action shall be signed by all members of the Committee
entitled to vote upon the action and such written consent is filed with the
records of the proceedings of the Committee.

                                  ARTICLE VI
                                   OFFICERS

   SECTION 6.1. Executive Officers. The executive officers of the Trust shall
be a Chairman, a President, one or more Vice Presidents, a Secretary and a
Treasurer. The Chairman shall be selected from among the Trustees but none of
the other executive officers need be a Trustee. Two or more offices, except
those of President and any Vice President, may be held by the same person,
but no officer shall execute,

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acknowledge or verify any instrument in more than one capacity. The executive
officers of the Trust shall be elected annually by the Trustees and each
executive officer so elected shall hold office until his or her successor is
elected and has qualified.

   SECTION 6.2. Other Officers and Agents. The Trustees may also elect one or
more Assistant Vice Presidents, Assistant Secretaries and Assistant
Treasurers and may elect, or may delegate to the Chairman the power to
appoint, such other officers and agents as the Trustees shall at any time or
from time to time deem advisable.

   SECTION 6.3. Term and Removal and Vacancies. Each officer of the Trust
shall hold office until his or her successor is elected and has qualified.
Any officer or agent of the Trust may be removed by the Trustees whenever, in
their judgment, the best interests of the Trust will be served thereby, but
such removal shall be without prejudice to the contractual rights, if any, of
the person so removed.

   SECTION 6.4. Compensation of Officers. The compensation of officers and
agents of the Trust shall be fixed by the Trustees, or by the Chairman to the
extent provided by the Trustees with respect to officers appointed by the
Chairman.

   SECTION 6.5. Powers and Duties. All officers and agents of the Trust, as
between themselves and the Trust, shall have such authority and perform such
duties in the management of the Trust as may be provided in or pursuant to
these By-Laws or, to the extent not so provided, as may be prescribed by the
Trustees; provided that no rights of any third party shall be affected or
impaired by any such By-Law or resolution of the Trustees unless such third
party has knowledge thereof.

   SECTION 6.6. The Chairman. The Chairman shall be the chief executive
officer of the Trust, shall preside at all meetings of the Shareholders and
of the Trustees, shall have general and active management of the business of
the Trust, shall see that all orders and resolutions of the Trustees are
carried into effect and, in connection therewith, shall be authorized to
delegate to the President or to one or more Vice Presidents such of his or
her powers and duties at such times and in such manner as he or she may deem
advisable, shall be a signatory on all Annual and Semi-Annual Reports as may
be sent to Shareholders, and shall perform such other duties as the Trustees
may from time to time prescribe.

   SECTION 6.7. The President. The President shall perform such duties as the
Trustees and the Chairman may from time to time prescribe and shall, in the
absence or disability of the Chairman, exercise the powers and perform the
duties of the Chairman. The President shall be authorized to delegate to one
or more Vice Presidents such of his or her powers and duties at such times
and in such manner as he or she may deem advisable.

   SECTION 6.8. The Vice Presidents. The Vice Presidents shall be of such
number and shall have such titles as may be determined from time to time by
the Trustees. The Vice President, or, if there shall be more than one, the
Vice Presidents in such order as may be determined from time to time by the
Trustees or the Chairman, shall, in the absence or disability of the
President, exercise the powers and perform the duties of the President, and
shall perform such other duties as the Trustees or the Chairman may from time
to time prescribe.

   SECTION 6.9. The Assistant Vice Presidents. The Assistant Vice President,
or, if there shall be more than one, the Assistant Vice Presidents in such
order as may be determined from time to time by the Trustees or the Chairman,
shall perform such duties and have such powers as may be assigned them from
time to time by the Trustees or the Chairman.

   SECTION 6.10. The Secretary. The Secretary shall attend all meetings of
the Trustees and all meetings of the Shareholders and record all the
proceedings of the meetings of the Shareholders and of the Trustees in a book
to be kept for that purpose, and shall perform like duties for the standing
committees when required. He or she shall give, or cause to be given, notice
of all meetings of the Shareholders and special meetings of the Trustees, and
shall perform such other duties and have such powers as the Trustees or the
Chairman may from time to time prescribe. He or she shall keep in safe
custody the seal of the Trust and affix or cause the same to be affixed to
any instrument requiring it, and, when so affixed, it shall be attested by
his or her signature or by the signature of an Assistant Secretary.

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   SECTION 6.11. The Assistant Secretaries. The Assistant Secretary, or, if
there shall be more than one, the Assistant Secretaries in such order as may
be determined from time to time by the Trustees or the Chairman, shall, in
the absence or disability of the Secretary, perform the duties and exercise
the powers of the Secretary and shall perform such duties and have such other
powers as the Trustees or the Chairman may from time to time prescribe.

   SECTION 6.12. The Treasurer. The Treasurer shall be the chief financial
officer of the Trust. He or she shall keep or cause to be kept full and
accurate accounts of receipts and disbursements in books belonging to the
Trust, and he or she shall render to the Trustees and the Chairman, whenever
any of them require it, an account of his or her transactions as Treasurer
and of the financial condition of the Trust, and he or she shall perform such
other duties as the Trustees or the Chairman may from time to time prescribe.

   SECTION 6.13. The Assistant Treasurers. The Assistant Treasurer, or, if
there shall be more than one, the Assistant Treasurers in such order as may
be determined from time to time by the Trustees or the Chairman, shall, in
the absence or disability of the Treasurer, perform the duties and exercise
the powers of the Treasurer and shall perform such other duties and have such
other powers as the Trustees or the Chairman may from time to time prescribe.

   SECTION 6.14. Delegation of Duties. Whenever an officer is absent or
disabled, or whenever for any reason the Trustees may deem it desirable, the
Trustees may delegate the powers and duties of an officer or officers to any
other officer or officers or to any Trustee or Trustees.

                                 ARTICLE VII
                         DIVIDENDS AND DISTRIBUTIONS

   Subject to any applicable provisions of law and the Declaration, dividends
and distributions upon the Shares may be declared at such intervals as the
Trustees may determine, in cash, in securities or other property, or in
Shares, from any sources permitted by law, all as the Trustees shall from
time to time determine.

   Inasmuch as the computation of net income and net profits from the sales
of securities or other properties for federal income tax purposes may vary
from the computation thereof on the records of the Trust, the Trustees shall
have power, in their discretion, to distribute as income dividends and as
capital gain distributions, respectively, amounts sufficient to enable the
Trust to avoid or reduce liability for federal income taxes.

                                 ARTICLE VIII
                            CERTIFICATES OF SHARES

   SECTION 8.1. Certificates of Shares. Certificates for Shares of each
series or class of Shares shall be in such form and of such design as the
Trustees shall approve, subject to the right of the Trustees to change such
form and design at any time or from time to time, and shall be entered in the
records of the Trust as they are issued. Each such certificate shall bear a
distinguishing number; shall exhibit the holder's name and certify the number
of full Shares owned by such holder; shall be signed by or in the name of the
Trust by the President, or a Vice President, and countersigned by the
Secretary or an Assistant Secretary or the Treasurer and an Assistant
Treasurer of the Trust; shall be sealed with the seal; and shall contain such
recitals as may be required by law. Where any certificate is signed by a
Transfer Agent or by a Registrar, the signature of such officers and the seal
may be facsimile, printed or engraved. The Trust may, at its option,
determine not to issue a certificate or certificates to evidence Shares owned
of record by any Shareholder.

   In case any officer or officers who shall have signed, or whose facsimile
signature or signatures shall appear on, any such certificate or certificates
shall cease to be such officer or officers of the Trust, whether because of
death, resignation or otherwise, before such certificate or certificates
shall have been delivered by the Trust, such certificate or certificates
shall, nevertheless, be adopted by the Trust and be issued and

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delivered as though the person or persons who signed such certificate or
certificates or whose facsimile signature or signatures shall appear therein
had not ceased to be such officer or officers of the Trust.

   No certificate shall be issued for any share until such share is fully
paid.

   SECTION 8.2. Lost, Stolen, Destroyed and Mutilated Certificates. The
Trustees may direct a new certificate or certificates to be issued in place
of any certificate or certificates theretofore issued by the Trust alleged to
have been lost, stolen or destroyed, upon satisfactory proof of such loss,
theft, or destruction; and the Trustees may, in their discretion, require the
owner of the lost, stolen or destroyed certificate, or his legal
representative, to give to the Trust and to such Registrar, Transfer Agent
and/or Transfer Clerk as may be authorized or required to countersign such
new certificate or certificates, a bond in such sum and of such type as they
may direct, and with such surety or sureties, as they may direct, as
indemnity against any claim that may be against them or any of them on
account of or in connection with the alleged loss, theft or destruction of
any such certificate.

                                  ARTICLE IX
                                  CUSTODIAN

   SECTION 9.1.  Appointment and Duties. The Trust shall at times employ a
bank or trust company having capital, surplus and undivided profits of at
least five million dollars ($5,000,000) as custodian with authority as its
agent, but subject to such restrictions, limitations and other requirements,
if any, as may be contained in these By-Laws and the 1940 Act:

     (1) to receive and hold the securities owned by the Trust and deliver
    the same upon written or electronically transmitted order;

     (2) to receive and receipt for any moneys due to the Trust and deposit
    the same in its own banking department or elsewhere as the Trustees may
    direct;

     (3) to disburse such funds upon orders or vouchers;

all upon such basis of compensation as may be agreed upon between the
Trustees and the custodian. If so directed by a Majority Shareholder Vote,
the custodian shall deliver and pay over all property of the Trust held by it
as specified in such vote.

   The Trustees may also authorize the custodian to employ one or more
sub-custodians from time to time to perform such of the acts and services of
the custodian and upon such terms and conditions as may be agreed upon
between the custodian and such sub-custodian and approved by the Trustees.

   SECTION 9.2. Central Certificate System. Subject to such rules,
regulations and orders as the Commission may adopt, the Trustees may direct
the custodian to deposit all or any part of the securities owned by the Trust
in a system for the central handling of securities established by a national
securities exchange or a national securities association registered with the
Commission under the Securities Exchange Act of 1934, or such other person as
may be permitted by the Commission, or otherwise in accordance with the 1940
Act, pursuant to which system all securities of any particular class or
series of any issuer deposited within the system are treated as fungible and
may be transferred or pledged by bookkeeping entry without physical delivery
of such securities, provided that all such deposits shall be subject to
withdrawal only upon the order of the Trust.

                                  ARTICLE X
                               WAIVER OF NOTICE

   Whenever any notice of the time, place or purpose of any meeting of
Shareholders, Trustees, or of any committee is required to be given in
accordance with law or under the provisions of the Declaration or these
By-Laws, a waiver thereof in writing, signed by the person or persons
entitled to such notice and filed with the records of the meeting, whether
before or after the holding thereof, or actual attendance at the meeting of
shareholders, Trustees or committee, as the case may be, in person, shall be
deemed equivalent to the giving of such notice to such person.

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                                  ARTICLE XI
                                MISCELLANEOUS

   SECTION 11.1. Location of Books and Records. The books and records of the
Trust may be kept outside the Commonwealth of Massachusetts at such place or
places as the Trustees may from time to time determine, except as otherwise
required by law.

   SECTION 11.2. Record Date. The Trustees may fix in advance a date as the
record date for the purpose of determining the Shareholders entitled to (i)
receive notice of, or to vote at, any meeting of Shareholders, or (ii)
receive payment of any dividend or the allotment of any rights, or in order
to make a determination of Shareholders for any other proper purpose. The
record date, in any case, shall not be more than one hundred eighty (180)
days, and in the case of a meeting of Shareholders not less than ten (10)
days, prior to the date on which such meeting is to be held or the date on
which such other particular action requiring determination of Shareholders is
to be taken, as the case may be. In the case of a meeting of Shareholders,
the meeting date set forth in the notice to Shareholders accompanying the
proxy statement shall be the date used for purposes of calculating the 180
day or 10 day period, and any adjourned meeting may be reconvened without a
change in record date. In lieu of fixing a record date, the Trustees may
provide that the transfer books shall be closed for a stated period but not
to exceed, in any case, twenty (20) days. If the transfer books are closed
for the purpose of determining Shareholders entitled to notice of a vote at a
meeting of Shareholders, such books shall be closed for at least ten (10)
days immediately preceding the meeting.

   SECTION 11.3. Seal. The Trustees shall adopt a seal, which shall be in
such form and shall have such inscription thereon as the Trustees may from
time to time provide. The seal of the Trust may be affixed to any document,
and the seal and its attestation may be lithographed, engraved or otherwise
printed on any document with the same force and effect as if it had been
imprinted and attested manually in the same manner and with the same effect
as if done by a Massachusetts business corporation under Massachusetts law.

   SECTION 11.4. Fiscal Year. The fiscal year of the Trust shall end on such
date as the Trustees may by resolution specify, and the Trustees may by
resolution change such date for future fiscal years at any time and from time
to time.

   SECTION 11.5. Orders for Payment of Money. All orders or instructions for
the payment of money of the Trust, and all notes or other evidences of
indebtedness issued in the name of the Trust, shall be signed by such officer
or officers or such other person or persons as the Trustees may from time to
time designate, or as may be specified in or pursuant to the agreement
between the Trust and the bank or trust company appointed as Custodian of the
securities and funds of the Trust.

                                 ARTICLE XII
                     COMPLIANCE WITH FEDERAL REGULATIONS

   The Trustees are hereby empowered to take such action as they may deem to
be necessary, desirable or appropriate so that the Trust is or shall be in
compliance with any federal or state statute, rule or regulation with which
compliance by the Trust is required.

                                 ARTICLE XIII
                                  AMENDMENTS

   These By-Laws may be amended, altered, or repealed, or new By-Laws may be
adopted, (a) by a Majority Shareholder Vote, or (b) by the Trustees;
provided, however, that no By-Law may be amended, adopted or repealed by the
Trustees if such amendment, adoption or repeal requires, pursuant to law, the
Declaration, or these By-Laws, a vote of the Shareholders. The Trustees shall
in no event adopt By-Laws which are in conflict with the Declaration, and any
apparent inconsistency shall be construed in favor of the related provisions
in the Declaration.

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                                 ARTICLE XIV
                             DECLARATION OF TRUST

   The Declaration of Trust establishing Morgan Stanley Dean Witter Municipal
Income Opportunities Trust, dated June 22, 1988, a copy of which, together
with all amendments thereto, is on file in the office of the Secretary of the
Commonwealth of Massachusetts, provides that the name Morgan Stanley Dean
Witter Municipal Income Opportunities Trust refers to the Trustees under the
Declaration collectively as Trustees, but not as individuals or personally;
and no Trustee, Shareholder, officer, employee or agent of Morgan Stanley
Dean Witter Municipal Income Opportunities Trust shall be held to any
personal liability, nor shall resort be had to their private property for the
satisfaction of any obligation or claim or otherwise, in connection with the
affairs of said Morgan Stanley Dean Witter Municipal Income Opportunities
Trust, but the Trust Estate only shall be liable.

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