Nicor Gas Company
                                                                      Form 10-K
                                                                   Exhibit 3.03

                                NICOR GAS COMPANY

                          AMENDED AND RESTATED BY-LAWS
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                                   ARTICLE I.

                              STOCK AND TRANSFERS.

SECTION 1. Each holder of fully paid stock shall be entitled to a certificate or
certificates of stock stating the number and class of shares, and the
designation of the series, if any, which such certificate represents. All
certificates of stock shall be signed by the Chairman, the President or a Vice
President and by the Secretary or the Treasurer or an Assistant Secretary or an
Assistant Treasurer, provided that in case any officer who has signed any
certificate shall have ceased to be such officer before such certificate is
issued, it may be issued by the Company with the same effect as if such officer
had not ceased to be such at the date of its issue. All certificates of stock
may be sealed with the seal of the Company or a facsimile of such seal.

SECTION 2. Shares of stock shall be transferable only on the books of the
Company, and, except as hereinafter provided or as otherwise required by law,
shall be transferred only upon proper endorsement and surrender of the
certificates theretofore issued therefor. If an outstanding certificate of stock
shall be lost, destroyed or stolen, the holder thereof may have a new
certificate upon producing evidence satisfactory to the Secretary or an
Assistant Secretary of the Company of such loss, destruction or theft, and, if
required by the Secretary or an Assistant Secretary upon furnishing to the
Company, a bond of indemnity deemed sufficient by the Secretary or an Assistant
Secretary, against claims under the outstanding certificate.

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SECTION 3. The
certificates for each class or series of stock shall be numbered and a record
shall be made of the name and address of the person to whom each certificate is
issued, the number of shares represented by the certificate and the number and
date of the certificate. All certificates exchanged or returned to the Company
for transfer shall be cancelled.

SECTION 4. For the purpose of determining
stockholders entitled to notice of or to vote at any meeting of stockholders, or
stockholders entitled to receive payment of any dividend, or in order to make a
determination of stockholders for any other proper purpose, the Board of
Directors may fix in advance a date as the record date for any such
determination of stockholders, such date in any case to be not more than sixty
days and, for a meeting of stockholders, not less than ten days, or in the case
of a merger, consolidation, share exchange, dissolution or sale, lease or
exchange of assets, not less than twenty days, immediately preceding such
meeting. If no record date is fixed for the determination of stockholders
entitled to notice of or to vote at a meeting of stockholders, or stockholders
entitled to receive payment of a dividend, the date on which notice of the
meeting is mailed or the date on which the resolution of the Board of Directors
declaring such dividend is adopted, as the case may be, shall be the record
date. When a determination of stockholders entitled to vote at any meeting of
stockholders has been made as provided in this Section, such determination shall
apply to any adjournment thereof.


                                  ARTICLE II.

                            MEETINGS OF STOCKHOLDERS.

SECTION 1. The regular annual meeting of the stockholders of the Company for the
election of Directors and for the transaction of such other business as may come
before the meeting shall be held on the third Thursday in April of each year, or
on such other date of each

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year as the Board of Directors may determine. Each
such regular annual meeting and each special meeting of the stockholders shall
be held at such place as the Board of Directors may determine.

SECTION 2. Special meetings of the stockholders may be called by the Chairman,
the President, the Board of Directors, a majority of the Directors individually
or the holders of not less than one-fifth of all the outstanding shares entitled
to vote on the matter for which the meeting is called.

SECTION 3. Written notice stating the place, day and hour of each meeting of the
stockholders and, in case of a special meeting, the purpose or purposes for
which the meeting is called, shall be delivered not less than ten nor more than
sixty days before the date of the meeting, or, in the case of a merger,
consolidation, share exchange, dissolution or sale, lease or exchange of assets
not less than twenty nor more than sixty days before the date of the meeting
either personally or by mail, by or at the direction of the Chairman, the
President, the Secretary or the persons calling the meeting, to each stockholder
of record entitled to vote at the meeting. If mailed, such notice shall be
deemed to be delivered when deposited in the United States mail addressed to the
stockholder at his address as it appears upon the records of the Company, with
postage thereon prepaid.

SECTION 4. At all meetings of the stockholders a majority of the
outstanding shares of stock entitled to vote on a matter, excluding such shares
as may be owned by the Company, represented in person or by proxy, shall
constitute a quorum for consideration of such matter at a meeting of
stockholders; provided that if less than a majority of the outstanding shares
are represented at the meeting, a majority of the shares so represented may
adjourn the meeting at any time without further notice. If a quorum is present,
the affirmative vote of a majority of the

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shares represented at the meeting and
entitled to vote on a matter shall be the act of the stockholders, unless the
vote of a greater number or voting by classes is required by The Business
Corporation Act of 1983 of the State of Illinois (hereinafter referred to as the
Act) or the Articles of Incorporation of the Company.

SECTION 5. At every meeting of the stockholders, each outstanding share of
stock regardless of class shall be entitled to one vote upon each matter voted
upon, and such vote may in all cases be given by proxy. In all elections for
Directors every stockholder shall have the right to vote, in person or by proxy,
the number of shares owned by him for as many persons as there are Directors to
be elected, or to cumulate such votes and give to one candidate as many votes as
shall equal the number of Directors to be elected multiplied by the number of
his shares of stock, or to distribute such cumulative votes in any proportion
among any number of candidates.

SECTION 6. Within twenty days after the record date for a meeting of
stockholders or ten days before such meeting, whichever is earlier, the
Secretary shall make a true and complete list, in alphabetical order, of all the
stockholders of the Company entitled to vote at the meeting, together with the
address of each and the number of shares held by each.

SECTION 7. The Chairman and the Secretary of the Company shall, when
present, act as Chairman and Secretary, respectively, of each meeting of the
stockholders.

                                  ARTICLE III.

                               BOARD OF DIRECTORS.

SECTION 1. Unless the Board of Directors determines otherwise, the number of
Directors of the Company shall be not less than eight nor more than thirteen.
The number of

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Directors may be fixed or changed from time to time within the
foregoing minimum and maximum by the Directors without further amendment of
these by-laws. The Directors shall be elected at each annual meeting of the
stockholders, but if for any reason the election shall not be held at an annual
meeting, it may be subsequently held at any special meeting of the stockholders
called for that purpose after proper notice. Each Director, including one
elected to fill a vacancy or elected as a result of an increase in the number of
Directors, shall hold office until the next succeeding annual meeting or until
his successor shall have been elected and qualified. Any vacancy occurring in
the Board of Directors and any directorship to be filled by reason of an
increase in the number of Directors may be filled by election at an annual
meeting or at a special meeting of stockholders called for that purpose;
provided, however, that any vacancy arising between meetings of stockholders by
reason of an increase in the number of Directors or otherwise may be filled by
the Board of Directors. A decrease in the number of Directors does not shorten
an incumbent Director's term. Directors need not be residents of the State of
Illinois or stockholders of the Company.

SECTION 2. Regular meetings of the
Board of Directors shall be held at such time and place as shall from time to
time be determined by the Board of Directors. Notice of such meeting, stating
the time and place at which it will be held, shall be given to each Director
personally, by telephone or by facsimile transmission at least one day, or by
depositing such notice in the mails properly addressed, at least two days before
the day of such meeting.

SECTION 3. Special meetings of the Board of Directors may be called at any time
by the Chairman, the President or by any two Directors and shall be held at such
place as shall be specified in the notice for such meeting. Notice of every
special meeting of the Board stating the time and place at which such meeting
will be held, shall be given to each Director personally, by

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telephone or by
facsimile transmission at least one day, or by depositing such notice in the
mails properly addressed, at least two days before the day of such meeting.

SECTION 4. A majority of the number of Directors then in office shall constitute
a quorum for the transaction of business at any meeting of the Board; provided
that if less than a quorum is present at the meeting, a majority of the
Directors present may adjourn the meeting at any time without further notice. At
all meetings of the Board of Directors at which a quorum is present, a majority
vote of those present shall be decisive of all questions before the meeting.

SECTION 5. The Board of Directors, by the affirmative vote of a majority of the
Directors then in office, and irrespective of any personal interest of any of
its members, shall have authority to establish reasonable compensation of all
Directors for services to the Company as Directors, officers or otherwise.

SECTION 6. Any action required to be taken at a meeting of the Board of
Directors, or any other action which may be taken at a meeting of the Board of
Directors or of any committee thereof, may be taken without a meeting if a
consent in writing, setting forth the action so taken, shall be signed by all of
the Directors entitled to vote with respect to the subject matter thereof, or by
all the members of such committee, as the case may be.

SECTION 7. Members of the Board of Directors or of any committee thereof may
participate in and act at any meeting of such Board or committee through the use
of a conference telephone or other communications equipment by means of which
all persons participating in the meeting can hear each other. Participation in
such a meeting shall constitute attendance and presence in person at the meeting
of the person or persons so participating.

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                                  ARTICLE IV.

                                  COMMITTEES.

SECTION 1. There shall be an Executive Committee of not less than five members
consisting of the Chairman of the Company, the President and not less than three
other Directors. The chairman of the Committee shall be the Chairman of the
Company or another Director elected or designated by the Board of Directors. The
Board of Directors shall, at its first meeting after the annual meeting of the
stockholders in each year, by resolution adopted by a majority of the number of
Directors then in office designate the chairman and the regular members of the
Committee and the remaining Directors who shall constitute alternates to serve
temporarily, and as far as practicable in rotation, as members of the Committee
in place of any of the regular members who, at any time, may be unable to serve.
The Chairman of the Company, the President or the Directors calling a meeting of
the Committee shall call upon alternates to serve as herein provided. When any
alternate serves, the minutes of the meeting shall record the name of the
regular member in whose place he serves. Each Director designated as a regular
member of the Executive Committee shall serve as such for one year or until his
successor shall have been designated. The Executive Committee shall, when the
Board is not in session, have and may exercise all of the authority of the Board
of Directors in the management of the Company, except as limited by Section 3 of
this Article IV. Vacancies in the membership of the Executive Committee shall be
filled by the Board of Directors. The Executive Committee shall keep minutes of
the proceedings at its meetings and such minutes shall be distributed to the
Directors at or before the next meeting of the Board thereafter.

SECTION 2. A majority of the number of the Directors then in office may from
time to time appoint, or authorize the appointment of, other committees,
standing or special, from among

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its own number and confer such powers upon such
committees, except as limited by Section 3 of this Article IV, and revoke such
powers and terminate the existence of such committees, as the Board at its
pleasure may determine. All such committees may have such number of members as
the Board of Directors designates.

SECTION 3. Neither the Executive Committee
nor any other committee of the Board of Directors shall (i) authorize
distributions, except for dividends to be paid with respect to shares of any
preferred or special classes or any series thereof; (ii) approve or recommend to
stockholders any act the Act requires to be approved by the stockholders; (iii)
fill vacancies on the Board or any of its committees; (iv) elect or remove
officers or fix the compensation of any member of the committee; (v) adopt,
amend or repeal the by-laws; (vi) approve a plan of merger not requiring
stockholder approval; (vii) authorize or approve the reacquisition of shares
except according to a general formula or method prescribed by the Board; (viii)
authorize or approve the issuance or sale, or contract for sale, of shares or
determine the designation and relative rights, preferences, and limitations of a
series of shares, except that the Board may direct a committee to fix the
specific terms of the issuance or sale or contract for sale or the number of
shares to be allocated to particular employees under an employee benefit plan;
or (ix) amend, alter, or repeal, or take any action inconsistent with any
resolution or action of the Board if the resolution or action of the Board
provides by its terms that it shall not be amended, altered or repealed by a
committee.

SECTION 4. Meetings of any committee may be called at any time by the Chairman
of the Company, the President, or by any Director who is a member of the
committee, and shall be held at such place as shall be designated in the notice
of such meeting. Notice of each committee meeting stating the time and place at
which such meeting will be held shall be given to each

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member of the committee
personally, by telephone or by facsimile transmission at least one day, or by
depositing such notice in the mails properly addressed, at least two days before
the day of such meeting. A majority of the members of a committee shall
constitute a quorum thereof; provided that if less than a quorum is present at a
meeting, a majority of the Directors present may adjourn the meeting at any time
without further notice. A majority vote of those present at each meeting of a
committee at which a quorum is present shall be decisive of all questions before
the meeting. Each member of a committee, not receiving a salary from the
Company, or any affiliated company, shall be paid such fee for attendance at
each meeting as the Board of Directors may from time to time by resolution
determine.

                                   ARTICLE V.

                                   OFFICERS.

SECTION 1. There shall be elected by the Board of Directors, at its first
meeting after the annual election of Directors in each year if practicable, the
following principal officers of the Company, namely: a Chairman, who shall be a
Director of the Company, a President, such number of Vice Presidents as the
Board at the time may decide upon, a Secretary and a Treasurer. The Chairman
and/or President can be the Chief Executive Officer as determined by the Board.
The Board may also provide for such other officers and prescribe for each of
them such duties as in its judgment may from time to time be desirable in the
conduct of the affairs of the Company. Any two or more offices may be held by
the same person; one person may be an assistant in any two or more offices. All
officers shall hold their respective offices until the first meeting of the
Board of Directors after the next succeeding annual election of Directors or
until their successors shall have been elected, but any officer may be removed
from office by the

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Board of Directors whenever in its judgment the best
interests of the Company will be served thereby.

SECTION 2. The Chairman shall,
when present, preside at all meetings of the stockholders and of the Board of
Directors. He shall also, when present, preside at all meetings of the Executive
Committee unless the Board has designated another Director as Chairman of such
Committee. . If the Chairman is designated as the Chief Executive Officer of the
Company, the Chairman shall have the general management and direction, subject
to the control of the Board of Directors and the Executive Committee, of the
affairs of the Company. He shall have power to appoint any and all officers,
agents and employees of the Company not required by these by-laws to be elected
or appointed directly by the Board of Directors. He shall have power to accept
the resignation of or to discharge any and all officers, agents and employees of
the Company not elected or appointed directly by the Board of Directors. When
the Board of Directors is not in session, he shall have power to accept the
resignation or suspend the authority of any and all officers, agents and
employees of the Company elected or appointed directly by the Board of
Directors, subject, however, to the pleasure of the Board of Directors at its
next meeting. He shall sign all papers and documents to which his signature may
be necessary or appropriate and shall have such other powers and duties as
usually devolve upon the chief executive officer of a corporation, and such
further powers and duties as may be prescribed for him by the Board of Directors
or the Executive Committee.

SECTION 3. The President shall act in a general
executive capacity. If the Chairman is designated as the Chief Executive
Officer, the President shall assist the Chairman in the administration and
operation of the Company's business and general supervision of its policies and
affairs. The President shall, in the absence of or because of the inability to
act of the

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Chairman, perform all duties of the Chairman and preside at all
meetings of stockholders and of the Board of Directors. The President may sign,
alone or with the Secretary, or an Assistant Secretary, or any other proper
officer of the Company authorized by the Board of Directors, certificates,
contracts, and other instruments of the Company as authorized by the Board of
Directors.
      If the President is designated as the Chief Executive Officer, the
President shall have the general management and direction, subject to the
control of the Board of Directors and the Executive Committee, of the affairs of
the Company. He shall have power to appoint any and all officers, agents and
employees of the Company not required by these by-laws to be elected or
appointed directly by the Board of Directors. He shall have power to accept the
resignation of or to discharge any and all officers, agents and employees of the
Company not elected or appointed directly by the Board of Directors. When the
Board of Directors is not in session, he shall have power to accept the
resignation or suspend the authority of any and all officers, agents and
employees of the Company elected or appointed directly by the Board of
Directors, subject, however, to the pleasure of the Board of Directors at its
next meeting. He shall sign all papers and documents to which his signature may
be necessary or appropriate and shall have such other powers and duties as
usually devolve upon the chief executive officer of a corporation, and such
further powers and duties as may be prescribed for him by the Board of Directors
or the Executive Committee. In the absence or disability of the Chairman, the
President shall have the powers and perform the duties of the Chairman.

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SECTION 4. Each of the Vice Presidents shall have such powers and duties
as may be prescribed for him by the Board of Directors, the Executive Committee,
the President, or the officer to whom he reports.

SECTION 5. The Secretary shall attend all meetings of the stockholders, of
the Board of Directors and of the Executive Committee, shall keep a true and
faithful record thereof in proper books to be provided for that purpose, and
shall have the custody and care of the corporate seal, records, minute books and
stock books of the Company, and of such other books and papers as in the
practical business operations of the Company shall naturally belong in the
office or custody of the Secretary or as shall be placed in his custody by order
of the Board of Directors or the Executive Committee. He shall keep a suitable
record of the addresses of stockholders and shall, except as may be otherwise
required by statute or these by-laws, sign and issue all notices required for
meetings of stockholders, of the Board of Directors and of the Executive
Committee. In the case of a special meeting of the stockholders called by the
requisite number of stockholders or by a majority of the Directors individually,
and in the case of a special meeting of the Board of Directors or a meeting of
the Executive Committee, called by any two Directors, the Secretary may, and if
so requested by the persons calling the meeting shall, include the names of such
persons in the notice of the meeting. He shall sign all papers to which his
signature may be necessary or appropriate, shall affix and attest the seal of
the Company to all instruments requiring the seal, and shall have such other
powers and duties as are commonly incidental to the office of Secretary and as
may be prescribed for him by the Board of Directors, the Executive Committee,
the Chief Executive Officer, or the officer to whom he reports.

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<PAGE>

SECTION 6. The Treasurer shall have such powers and duties as are commonly
incidental to the office of Treasurer and as may be prescribed for him by the
Board of Directors, the Executive Committee, the Chief Executive Officer, or the
officer to whom he reports.

SECTION 7. Assistant officers may be elected by the Board of Directors or
appointed by the Chief Executive Officer or the President. Each assistant
officer shall assist the officer whom he is elected or appointed to assist and
shall for such purpose have the powers of such officer. In the absence or
disability of any officer, his duties shall, except as otherwise ordered by the
Board of Directors or Executive Committee, temporarily devolve upon such
assistant officer as shall be designated by the Chief Executive Officer.


                                   ARTICLE I.

                                 MISCELLANEOUS.

SECTION 1. Whenever any notice is required to be given under the provision of
these by-laws or under the provisions of the Articles of Incorporation of the
Company or under the provisions of the Act, a waiver thereof in writing, signed
by the person or persons entitled to such notice, whether before or after the
time stated therein, shall be deemed equivalent to the giving of such notice.
Attendance at any meeting shall constitute waiver of notice thereof unless the
person at the meeting objects to the holding of the meeting because proper
notice was not given.

SECTION 2. Any and all shares of stock of any corporation
owned by the Company and any and all voting trust certificates owned by the
Company calling for or representing shares of stock of any corporation may be
voted at any meeting of the stockholders of such corporation or at any meeting
of the holders of such certificates, as the case may be, by the Chairman, the
President, a Vice President, the Secretary or the Treasurer upon any question
which may be

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presented at such meeting, and any such officer may, on behalf of
the Company, waive any notice required to be given of the calling of such
meeting without notice. The Chairman, the President, a Vice President, the
Secretary and the Treasurer shall have authority to give to any person a written
proxy in the name of the Company and under its corporate seal, to vote any or
all shares of stock or any or all certificates owned by the Company upon any
question that may be presented at any such meeting of stockholders or
certificate holders, with full power to waive any notice of the calling of such
meeting and consent to the holding of such meeting without notice.

SECTION 3. The fiscal year of the Company shall begin on the first day of
January and end on the last day of December in each year.

                                  ARTICLE II.

                         AMENDMENT OR REPEAL OF BY-LAWS.

      These by-laws may be made, altered, amended or repealed by the
stockholders or the Board of Directors.

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