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                                                                     EXHIBIT 3.1


                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                               THOMAS GROUP, INC.


         The undersigned, J. Thomas Williams, certifies that he is the President
of Thomas Group, Inc., a corporation organized and existing under the laws of
the State of Delaware (the "Corporation"), and does hereby further certify as
follows:

         (1) The name of the Corporation is Thomas Group, Inc.

         (2) The name under which the Corporation was originally incorporated
was "Thomas Group, Inc." and the original Certificate of Incorporation of the
Corporation was filed with the Secretary of State of the State of Delaware on
June 12, 1978.

         (3) This Amended and Restated Certificate of Incorporation was duly
adopted in accordance with the provisions of Sections 242 and 245 of the General
Corporation Law of the State of Delaware.

         (4) This Amended and Restated Certificate of Incorporation restates and
integrates previous provisions and also amends the provisions of the
Corporation's Certificate of Incorporation.

         (5) The text of the Amended and Restated Certificate of Incorporation
of the Corporation, as amended hereby, is restated to read in its entirety, as
follows:

         First: The name of the Corporation is Thomas Group, Inc.

         Second: The address of the registered office of the Corporation in the
State of Delaware is 1209 Orange Street in the City of Wilmington, County of New
Castle. The name of its registered agent at such address is The Corporation
Trust Company.

         Third: The purpose of the Corporation is to engage in any lawful act or
activity for which a Corporation may be organized under the General Corporation
Law of the State of Delaware, as amended (the "DGCL").

         Fourth: 1. Authorized Shares. The total number of shares of stock which
the Corporation shall have authority to issue is 26,200,000, consisting of:

                  (a) 25,000,000 shares of Common Stock, par value $.01 per
         share ("Common Stock"); and

                  (b) 1,200,000 shares of Class B Common Stock, par value $.01
         per share ("Class B Stock").



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                         2. Provisions Relating to the Common Stock and Class B
Stock.

                         (a) Except as otherwise required by law, and subject to
         any special voting rights which may be conferred upon any class or
         series of stock of the Corporation, each holder of Common Stock shall
         be entitled to one vote for each share of the Common Stock standing in
         such holder's name on the records of the Corporation on each matter
         submitted to a vote of the stockholders. Except as required by law, the
         holders of the Class B Stock shall have no voting rights whatsoever.

                         (b) Subject to the rights of the holders of any class
         or series of stock of the Corporation, the holders of the Common Stock
         shall be entitled to receive when, as, and if declared by the Board of
         Directors of the Corporation, out of funds legally available therefor,
         dividends payable in cash, stock, or otherwise.

                         (c) Upon any liquidation, dissolution, or winding up of
         the Corporation, whether voluntary or involuntary, and after the
         holders of any class or series of stock of the Corporation having a
         preference over the Common Stock and Class B Stock with respect to
         distributions of assets upon any such liquidation, distribution or
         winding up, and any bonds, debentures, or other obligations of the
         Corporation shall have been paid in full the amounts to which they
         shall be entitled (if any), or a sum sufficient for such payment in
         full shall have been set aside, the remaining net assets of the
         Corporation shall be distributed pro rata to the holders of the Common
         Stock and Class B Stock, to the exclusion of the holders of shares of
         any other class or series of stock and any bonds, debentures, or other
         obligations of the Corporation.

         Fifth: Any action required or permitted to be taken by the stockholders
of the Corporation (including without limitation the election of Directors)
shall be effected at an annual or special meeting of stockholders of the
Corporation and may not be effected by any consent in writing by such
stockholders.

         Sixth: In furtherance and not in limitation of the powers conferred by
statute, the Board of Directors is expressly authorized:

                         1. To make, alter or repeal the bylaws of the
         Corporation;

                         2. To authorize and cause to be executed mortgages and
         liens upon the real and personal property of the Corporation;

                         3. To set apart out of any of the funds of the
         Corporation available for dividends a reserve or reserves for any
         proper purpose and to abolish any such reserve in the manner in which
         it was created;





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                         4. By a majority of the whole Board of Directors, to
         designate one or more committees, each committee to consist of one or
         more of the Directors of the Corporation. The Board of Directors may
         designate one or more Directors as alternate members of any committee,
         who may replace any absent or disqualified member at any meeting of the
         committee. Any such committee, to the extent provided in the resolution
         or in the bylaws of the Corporation and permitted by law, shall have an
         may exercise the powers of the Board of Directors in the management of
         the business and affairs of the Corporation and may authorize the seal
         of the Corporation to be affixed to all papers which may require it.
         The bylaws may provide that in the absence or disqualification of any
         member of such committee or committees the member or members thereof
         present at any meeting and not disqualified from voting whether or not
         he or they constitute a quorum, may unanimously appoint another member
         of the Board of Directors to act at the meeting in the place of any
         such absent or disqualified member; and

                         5. When and as authorized by the affirmative vote of
         the holders of a majority of the stock issued and outstanding having
         voting power given at a stockholders' meeting duly called upon such
         notice as is required by statute, sell, lease or exchange all or
         substantially all of the property and assets of the Corporation,
         including its goodwill and its corporate franchises, upon such terms
         and conditions and for such consideration, which may consist in whole
         or in part of money or property including securities of any other
         corporation or corporations, as the Board of Directors shall deem
         expedient and for the best interests of the Corporation.

         Seventh: No contract or transaction between the Corporation and one or
more of its Directors, officers or stockholders or between the Corporation and
any person (as used herein "person" means other corporation, partnership,
association, firm, trust, joint venture, political subdivision or
instrumentality) or other organization in which one or more of its directors,
officers or stockholders are directors, officers, or stockholders, or have a
financial interest, shall be void or voidable solely for this reason, or solely
because the Director or officer is present at or participates in the meeting of
the Board or committee which authorizes the contract or transaction, or solely
because his, her or their votes are counted for such purpose; if: (i) the
material facts as to his or her relationship or interest as to the contract or
transaction are disclosed or are known to the Board of Directors or the
committee, and the Board of Directors or committee in good faith authorizes the
contract or transaction by the affirmative votes of a majority of the
disinterested Directors, even though the disinterested Directors be less than a
quorum; or (ii) the material facts as to his or her relationship or interest and
as to the contract or transaction are disclosed or are known to the stockholders
entitled to vote thereon, and the contract or transaction is specifically
approved in good faith by vote of the stockholders; or (iii) the contract or
transaction is fair as to the Corporation as of the time it is authorized,
approved or ratified by the Board of Directors, a committee thereof, or the
stockholders. Common or interested Directors may be counted in determining the
presence of a quorum at a meeting of the Board of Directors or of a committee
which authorizes the contract or transaction.

         Eighth: 1. Indemnification of Officers and Directors. The Corporation
         shall indemnify 



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         any person who was, is, or is threatened to be made a party to a
         proceeding (as hereinafter defined) by reason of the fact that he or
         she (i) is or was a Director or officer of the Corporation or (ii)
         while a Director or officer of the Corporation, is or was serving at
         the request of the Corporation as a director, officer, partner,
         venturer, proprietor, trustee, employee, agent or similar functionary
         of another foreign or domestic corporation partnership, joint venture,
         sole proprietorship, trust, employee benefit plan or other enterprise,
         to the fullest extent permitted under the DGCL, as the same exists or
         may hereafter be amended. Such right shall be a contract right and as
         such shall run to the benefit of any Director or officer who is elected
         and accepts the position of Director or officer of the Corporation or
         elects to continue to serve as a Director or officer of the Corporation
         or elects to continue to serve as a Director or officer of the
         Corporation while this Article 10 is in effect. Any repeal or amendment
         of this Article 10 shall be prospective only and shall not limit the
         rights of any such Director or officer in any of the foregoing
         capacities prior to any such repeal or amendment to this Article 10.
         Such right shall include the right to be paid by the Corporation
         expenses incurred in defending any such proceeding in advance of its
         final disposition to the maximum extent permitted under the DGCL, as
         the same exists or may hereafter be amended. If a claim for
         indemnification or advancement of expenses hereunder is not paid in
         full by the Corporation within sixty (60) days after a written claim
         has been received by the Corporation, the claimant may at any time
         thereafter bring suit against the Corporation to recover the unpaid
         amount of the claim, and if successful in whole or in part, the
         claimant shall also be entitled to be paid the expenses of prosecuting
         such claim. It shall be a defense to any such action that such
         indemnification or advancement of costs of defense are not permitted
         under the DGCL, but the burden of proving such defense shall be on the
         Corporation. Neither the failure of the Corporation (including its
         Board of Directors or any committee thereof, independent legal counsel,
         or stockholders to have made its determination prior to the
         commencement of such action that indemnification of, or advancement of
         costs of defense to, the claimant is permissible in the circumstances
         nor an actual determination by the Corporation (including its Board of
         Directors or any committee thereof, independent counsel, or
         stockholders) that such indemnification or advancement is not
         permissible. In the event of the death of any person having a right of
         indemnification under the foregoing provisions, such right shall inure
         to the benefit of his or her heirs, executors, administrators, and
         personal representatives. The rights conferred above shall not be
         exclusive of any other right which any person may have or hereafter
         acquire under any statute, by law, resolution of stockholders or
         Directors, agreement, or otherwise.

                         2. Indemnification of Employees or Agents of the
         Corporation. The Corporation may additionally indemnify any employee or
         agent of the Corporation to the fullest extent permitted by law.

                         3. Judicial Proceedings. As used herein, the term
         "proceeding" means any threatened, pending, or completed action, suit
         or proceeding, whether civil, criminal, administrative, arbitrative or
         investigative, any appeal in such an action, suit or 




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         proceeding, and any inquiry or investigation that could lead to such an
         action, suit, or proceeding; provided, however, "proceeding" shall not
         include any proceeding, action or suit commenced by or on behalf of the
         person seeking indemnification or advancement of expenses unless such
         proceeding was approved in advance by the Corporation's Board of
         Directors.

         Ninth: Whenever a compromise or arrangement is proposed between this
Corporation and its creditors or any class of them and/or between this
Corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this Corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this Corporation under
the provisions of section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this Corporation under the provisions of section 279 of Title 8 of the
Delaware Code order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this Corporation, as the case may
be, to be summoned in such manner as the said court directs. If a majority in
number representing three-fourths (3/4) in value of the creditors or class of
creditors, and/or the stockholders or class of stockholders of this Corporation,
as the case may be, agree to any compromise or arrangement and to any
reorganization of this Corporation as consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application shall, if
sanctioned by the court to which the said application has been made, be binding
on all the creditors or class of creditors, and/or on all the stockholders or
class of stockholders, of this Corporation, as the case may be, and also on this
Corporation.

         Tenth: Meetings of stockholders may be held within or without the State
of Delaware, as the bylaws may provide. The books of the Corporation may be kept
(subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designed from time to time by the
Board of Directors or in the bylaws of the Corporation. Elections of Directors
need not be by written ballot unless the bylaws of the Corporation shall so
provide.

         Eleventh: The Corporation is to have perpetual existence.

         Twelfth: The Corporation reserves the right to amend, alter, change or
repeal any provision contained in this Certificate of Incorporation, in the
manner, now or hereafter prescribed herein or by statute, and all rights
conferred upon stockholders herein are granted subject to this reservation.

         Thirteenth: No Director of the Corporation shall be liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a Director, except for liability (i) for any breach of the Director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or that involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the DGCL or (iv) for any
transaction from which the Director



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derived an improper personal benefit. If the DGCL hereafter is amended to
authorize the further elimination or limitation of the liability of Directors,
then the liability of a Director of the Corporation, in addition to the
limitation on personal liability provided herein , shall be limited to the
fullest extent permitted by the amended DGCL. Any repeal or modification of this
Article by the stockholders of the Corporation shall be prospective only and
shall not adversely affect any limitation on the personal liability of a
Director of the Corporation existing at the time of such repeal or modification.

         Fourteenth: The Corporation expressly elects to be governed by Section
203 of the DGCL.

         Fifteenth: Notwithstanding any provisions of the Corporation's bylaws
to the contrary, the affirmative vote of the holders of at least two-thirds
(2/3) of the outstanding shares of each class of capital stock of the
Corporation then entitled to vote thereon shall be required to amend, alter or
repeal, or adopt any provision inconsistent with, Article II, Section 3 of the
Corporation's bylaws; Article II, Section 10 of the Corporation's bylaws; or
Article III, Section 4 of the Corporation's bylaws.

         Sixteenth: Notwithstanding any other provisions of this Certificate of
Incorporation or any provision of law which might otherwise permit a lesser vote
or no vote, the affirmative vote of the holders of at least two-thirds (2/3) of
the outstanding shares of each class of capital stock of the Corporation then
entitled to vote thereon shall be required to amend, alter or repeal, or adopt
any provisions inconsistent with any one or more of Articles Fifth, Eighth,
Twelfth, Thirteenth, Fourteenth, Fifteenth and Sixteenth of this Certificate of
Incorporation.


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         IN WITNESS WHEREOF, Thomas Group, Inc. has caused its corporate seal to
be hereunto affixed and this Amended and Restated Certificate of Incorporation
to be signed by J. Thomas Williams, its President, and attested by Roger A.
Crabb, its Secretary, on July 9, 1998.


THOMAS GROUP, INC.



By:
   ----------------------------------  
   J. Thomas Williams, President

ATTEST:


------------------------------------
   Roger A. Crabb, Secretary







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