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                                                                    EXHIBIT 3.1


                     RESTATED CERTIFICATE OF INCORPORATION

                                      OF

                         MORRISON KNUDSEN CORPORATION
                             (AS OF APRIL 8, 1998)



                                  ARTICLE I.

         The name of the Corporation is Morrison Knudsen Corporation.



                                  ARTICLE II.

          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, 19805.  The name of its registered agent at such address is The
Corporation Trust Company.



                                 ARTICLE III.

          The nature of the business or purposes to be conducted or promoted is
to engage in any lawful act or activity for which a corporation may now or
hereafter be organized under the General Corporation Law of the State of
Delaware as set forth in Title 8 of the Delaware Code (the "GCL").

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                                  ARTICLE IV.

          Section 1.  Authorized Capital Stock.  The total number of shares of
                      ------------------------                                
all classes of stock which the Corporation shall have authority to issue is One
Hundred Ten Million (110,000,000), consisting of One Hundred Million
(100,000,000) shares of common stock, par value $0.01 per share (the "Common
Stock"), and Ten Million (10,000,000) shares of preferred stock, par value $0.01
per share (the "Preferred Stock").

          Section 2.  Preferred Stock.  The Preferred Stock may be issued in one
                      ----------------                                          
or more series.  The Board of Directors of the Corporation is hereby authorized
to issue the shares of Preferred Stock in such series and to fix from time to
time before issuance the number of shares to be included in any series and the
designation, relative powers, preferences, and rights and qualifications,
limitations, or restrictions of all shares of a series.

          a.  Authority of the Board of Directors.  The authority of the Board
              -----------------------------------                             
     of Directors with respect to each series will include, without limiting the
     generality of the foregoing, the determination of any or all of the
     following:

              (i)   the distinctive designation of and the number of shares
          comprising the series, which number may be increased (except where
          otherwise provided by the Board of Directors in creating the series)
          or decreased (but not below the number of such shares then
          outstanding) from time to time by like action of the Board of
          Directors;

              (ii)  the voting powers, if any, and whether such voting powers
          are full or limited in such series;

              (iii) the redemption provisions, if any, applicable to the
          series, including the redemption price or prices to be paid;

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              (iv)   whether dividends, if any, will be cumulative or
          noncumulative, the dividend rate of the series, and the dates and
          preferences of dividends on the series;

              (v)    the rights of the series upon the voluntary or involuntary
          dissolution of, or upon any distribution of the assets of, the
          Corporation;

              (vi)   the provisions, if any, pursuant to which the shares of the
          series are convertible into, or exchangeable for, shares of any other
          class or classes or of any other series of the same or any other class
          or classes of stock, or any other security, of the Corporation or any
          other corporation or other entity, and the price or prices or the
          rates of exchange applicable thereto;

              (vii)  the right, if any, to subscribe for or to purchase any
          securities of the Corporation or any other corporation or other
          entity;

              (viii) the provisions, if any, of a sinking fund applicable to
          the series; and

              (ix)   any other relative, participating, optional, or other
          special powers, preferences, rights, qualifications, limitations, or
          restrictions thereof;

     all as may be determined from time to time by the Board of Directors and
     stated in the resolution or resolutions providing for the issuance of the
     Preferred Stock (collectively, a "Preferred Stock Designation").

          b.  Series A Preferred Stock.  The following is a statement of the
              ------------------------                                      
     powers, preferences, rights, qualifications, limitations and restrictions
     of the series of Preferred Stock designated as Series A Preferred Stock.

              (i)    Designation and Amount.  The shares of such series of
                     ----------------------                               
          Preferred Stock shall be designated as "Series A Preferred Stock" and
          the number of shares constituting such series shall be 1,800,000.

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              (ii)   Rank.  With respect to rights on liquidation, winding up 
                     ----
          and dissolution, the Series A Preferred Stock ranks (i) senior to both
          the Corporation's Common Stock and to all classes and series of stock
          of the Corporation now or hereafter authorized, issued or outstanding
          which by their terms expressly provide that they are junior to the
          Series A Preferred Stock as to distributions upon the liquidation,
          winding up and dissolution of the Corporation or which do not specify
          their rank (collectively with the Common Stock, the "Junior
          Securities"); (ii) on a parity with each other class or series of
          capital stock issued by the Corporation after the date hereof the
          terms of which specifically provide that such class or series will
          rank on a parity with the Series A Preferred Stock as to distributions
          upon the liquidation, winding up and dissolution of the Corporation
          (collectively referred to as "Parity Securities"), provided that any
                                                             --------         
          such Parity Securities that were not approved by the holders of Series
          A Preferred Stock in accordance with paragraph (b)(vii)(B) of this
          Section 2 shall be deemed to be Junior Securities and not Parity
          Securities; and (iii) junior to each other class of capital stock or
          other series of Preferred Stock issued by the Corporation after the
          date hereof the terms of which have been approved by the holders of
          the Series A Preferred Stock in accordance with paragraph (b)(vii)(B)
          of this Section 2 and which specifically provide that such class or
          series will rank senior to the Series A Preferred Stock as to
          distributions upon the liquidation, winding up and dissolution of the
          Corporation (collectively referred to as "Senior Securities").

              (iii)  Dividends.  The holders of shares of Series A Preferred
                     ---------                                              
          Stock are not entitled to receive dividends.
               
              (iv)   Foreign Tax Credit Sinking Fund; Redemption.
                     ------------------------------------------- 
                     (A)    The Corporation shall create and maintain a sinking
               fund ("Foreign Tax Credit Sinking Fund") into which it shall
               deposit promptly upon 

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               receipt and hold all amounts received by the Corporation in
               respect of refunds of federal income tax and interest thereon
               associated with amended federal income tax returns of the
               Corporation and consolidated subsidiaries for the calendar years
               1982 through 1990 which were filed prior to January 1, 1996,
               which change the Corporation's election from deducting foreign
               taxes to claiming a credit for those taxes ("Foreign Tax Credit
               Refunds"); provided, however, that the cumulative total amount of
               Foreign Tax Credit Refunds, together with any amounts contributed
               pursuant to the sentence prior to the penultimate sentence of
               this paragraph, which the Corporation may deposit to the Sinking
               Fund shall not exceed $18,000,000. A majority of the directors of
               the Corporation present at a meeting at which a quorum is present
               has the exclusive power and authority to determine, in good
               faith, on the basis of information known to them after reasonable
               inquiry, (i) whether funds received by the Corporation are
               Foreign Tax Credit Refunds and (ii) the amount of any Foreign Tax
               Credit Refunds. The holders of the Series A Preferred Stock shall
               have no right to challenge any such determination unless such
               challenge is specifically authorized by the beneficial owners of
               a majority of the issued and outstanding shares of the Series A
               Preferred Stock. The Corporation may, but shall not be obligated
               to, deposit funds other than Foreign Tax Credit Refunds into the
               Foreign Tax Credit Sinking Fund; provided, however, that such a
                                                --------  -------             
               deposit of funds other than Foreign Tax Credit Refunds shall be
               made only upon the affirmative vote of two-thirds of the total
               number of directors that the Corporation would have if there were
               no vacancies.  Pending distribution of the amounts in the Foreign
               Tax Credit Sinking Fund pursuant to paragraph (b)(iv)(B) of this
               Section 2, all such amounts shall be 

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               deposited into and maintained in an interest-bearing account at a
               bank or other depository institution at which the Corporation
               maintains other interest-bearing deposit accounts. Other than
               distributions made pursuant to paragraph (b)(iv)(B) of this
               Section 2, the Corporation shall not withdraw any funds from the
               Foreign Tax Credit Sinking Fund.

                    (B)    On the fifteenth day of the month following the end
               of each calendar quarter, the Corporation shall distribute to
               each holder of record of Series A Preferred Stock as of the last
               day of such calendar quarter an amount per share equal to a pro
               rata portion of (i) the total amount of Foreign Tax Credit
               Refunds deposited into the Foreign Credit Sinking Fund during the
               quarter and (ii) all interest earned on such total amount during
               the quarter. The distribution for the calendar quarter in which
               the cumulative total deposits to the sinking fund reaches
               $18,000,000 will be the final distribution with respect to the
               Series A Preferred Stock. Upon this final distribution, all
               shares of Series A Preferred Stock will be canceled and no longer
               outstanding and will not have the status of shares of Series A
               Preferred Stock, and all rights of the holders thereof as
               stockholders of the Corporation will cease.

                    (C)    If the Series A Preferred Stock has not been canceled
               as provided in paragraph (b)(iv)(B) of this Section 2 by the
               fifth anniversary of the issuance of the Series A Preferred
               Stock, the Corporation shall, on the fifteenth day ("Redemption
               Date") of the month following the fifth anniversary of the
               issuance of the Series A Preferred Stock, redeem all the
               outstanding shares of Series A Preferred Stock at a per share
               redemption price ("Redemption Price") equal to the greater of (I)
               $0.01, or (II) a pro rata portion of the balance of the Foreign
               Tax 

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               Credit Sinking Fund (including all interest earned thereon)
               as of the fifth anniversary of the issuance of the Series A
               Preferred Stock.

                    (D)    In the event that the Corporation redeems shares of
               Series A Preferred Stock pursuant to paragraph (b)(iv)(C) of this
               Section 2, the Corporation shall send notice of the redemption by
               first-class mail, postage prepaid, not less than 30 days prior to
               the Redemption Date, to the holders of record of the shares to be
               redeemed at their respective addresses as they shall appear in
               the records of the Corporation; provided, however, that failure
                                               --------  -------              
               to give such notice or any defect therein or in the mailing
               thereof shall not affect the validity of the proceedings for the
               redemption of any shares so to be redeemed except as to the
               holder to whom the Corporation has failed to give such notice or
               except as to the holder to whom notice was defective.  Each such
               notice shall state:  (i) the Redemption Date; (ii) the number of
               shares of Preferred Stock to be redeemed; (iii) the Redemption
               Price, and (iv) the place or places where certificates for such
               shares are to be surrendered for payment of the Redemption Price.
               Upon surrender of the certificates for the shares (properly
               endorsed or assigned for transfer, if the Board of Directors so
               requires and a notice by the Corporation so states), the
               Corporation shall redeem such shares at the Redemption Price as
               aforesaid.

                    (E)    If the Corporation has mailed the notice provided in
               paragraph (b)(iv)(D) of this Section 2, then, from and after the
               Redemption Date (unless the Corporation defaults in the payment
               of the Redemption Price, in which case such rights shall continue
               until the Redemption Price is paid), all shares of Series A
               Preferred Stock will be deemed to be cancelled and no longer
               outstanding, and will not have the status of shares of Series A
               Preferred Stock, and all rights of the 

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               holders thereof as stockholders of the Corporation (except the
               right to receive the Redemption Price) will cease.

               (v)   Liquidation Preference.
                     ---------------------- 

                     (A)   In the event of any voluntary or involuntary
               liquidation, dissolution or winding up of the affairs of the
               Corporation, each holder of outstanding shares of Series A
               Preferred Stock will be entitled to be paid out of the assets of
               the Corporation available for distribution to its stockholders,
               before any payment is made or any assets distributed to the
               holders of any of the Junior Securities, an amount in cash per
               share of Series A Preferred Stock held equal to the greater of
               (I) $0.01, or (II) a pro rata portion of the remaining balance of
               the Foreign Tax Credit Sinking Fund (including all interest
               earned thereon).  If the assets of the Corporation are not
               sufficient to pay in full the liquidation payments payable to the
               holders of outstanding shares of the Series A Preferred Stock and
               any Parity Securities, then the holders of all such shares shall
               share ratably in such distribution of assets in accordance with
               the amount which would be payable on such distribution if the
               amounts to which the holders of outstanding shares of Series A
               Preferred Stock and the holders of outstanding shares of such
               Parity Securities are entitled were paid in full.

                     (B)   For the purposes of this paragraph (b)(v), neither
               the voluntary sale, conveyance, exchange or transfer (for cash,
               shares of stock, securities or other consideration) of all or
               substantially all of the property or assets of the Corporation
               nor the consolidation or merger of the Corporation with any one
               or more other corporations shall be deemed to be a voluntary or
               involuntary liquidation, dissolution or winding up of the
               Corporation, unless such voluntary sale, 

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               conveyance, exchange or transfer shall be in connection with a
               plan of liquidation, dissolution or winding up of the
               Corporation.

               (vi)   Reacquired Shares.  Shares of Series A Preferred Stock 
                      ----------------- 
          that have been issued and reacquired by the Corporation in any manner,
          including shares reacquired by redemption pursuant to paragraph
          (b)(iv) of this Section 2, shall (upon compliance with any applicable
          provisions of the laws of the State of Delaware) have the status of
          authorized and unissued shares of Preferred Stock undesignated as to
          series, and may be redesignated and reissued as part of any series of
          Preferred Stock.

               (vii)  Voting Rights.  In addition to any voting rights provided
                      -------------                                            
          by law, the holders of Series A Preferred Stock have the following
          voting rights:

                     (A)   General.  Except as required in this Article IV and 
                           -------                              
               as otherwise required by law, shares of Series A Preferred Stock
               shall vote together with shares of Common Stock of the
               Corporation as a single class on all matters as to which the
               shares of Common Stock are entitled to vote generally.  Each
               share of Series A Preferred Stock is entitled to 1/10,000 of a
               vote.

                     (B)   Voting Rights On Extraordinary Matters.  In 
                           --------------------------------------  
               addition to any vote or consent of stockholders required by law,
               the approval of holders of at least two-thirds of the outstanding
               shares of Series A Preferred Stock, voting as a class, is
               required (i) to reclassify any series of Junior Securities as
               Senior Securities or Parity Securities, or (ii) to amend, repeal
               or change any of the provisions of this Restated and Amended
               Certificate of Incorporation or the provisions of this Article IV
               in any manner that would alter or change the rights, powers,
               preferences or privileges of the shares of Series A Preferred
               Stock so as to affect them adversely, including, without
               limitation, changing the voting percentage 

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               required for approval by the holders of Series A Preferred Stock
               of the foregoing matters.

                                  ARTICLE V.

          The business and affairs of the Corporation shall be managed by or
under the direction of the Board of Directors, which shall consist of not less
than six directors nor more than 12 directors, the exact number of directors to
be determined from time to time by resolution adopted by the Board of Directors.
At each annual meeting of the stockholders of the Corporation, commencing with
the 1998 annual meeting, all directors will be elected to serve for a term
expiring at the next annual meeting of the stockholders of the Corporation.  A
director shall hold office until the annual meeting at which his or her term
expires and until his or her successor shall be elected and shall qualify,
subject, however, to prior death, resignation, retirement, disqualification or
removal from office.  Any vacancy on the Board of Directors, howsoever
resulting, may be filled by a majority of the directors then in office, even if
less than a quorum, or by a sole remaining director.  Any director elected to
fill a vacancy shall hold office for a term expiring at the next annual meeting
of the stockholders of the Corporation.  Notwithstanding anything to the
contrary in this Restated and Amended Certificate of Incorporation or any
provision of Bylaws of the Corporation, there shall be no cumulative voting.

                                  ARTICLE VI.

          Any or all of the directors of the Corporation may be removed from the
Board of Directors, with or without cause, by the affirmative vote of the
holders of a majority of the voting power of the outstanding shares of voting
stock of the Corporation entitled to vote thereon.

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                                 ARTICLE VII.

          Elections of directors at an annual or special meeting of stockholders
need not be by written ballot unless the Bylaws of the Corporation shall
otherwise provide.

                                 ARTICLE VIII.

          Special meetings of the stockholders of the Corporation for any
purpose or purposes may be called at any time only by a majority of the Board of
Directors or the Chief Executive Officer or the President.

                                  ARTICLE IX.

          Any action which may be taken by stockholders of the Corporation at an
annual or special meeting may not be effected except at such an annual or
special meeting by the vote required for the taking of such action, and the
right of stockholders to act by written consent is expressly denied.

                                  ARTICLE X.

          The officers of the Corporation shall be chosen in such a manner,
shall hold their offices for such terms and shall carry out such duties as are
determined by the Board of Directors, subject to the right of the Board of
Directors to remove any officer or officers at any time with or without cause.

                                  ARTICLE XI.

          A.  The Corporation shall indemnify to the full extent authorized or
permitted by law (as now or hereafter in effect) any person made, or threatened
to be made, a defendant or witness to any action, suit or proceeding (whether
civil or criminal or otherwise) by reason of the fact that he, his testator or
intestate, is or was a director or officer of the Corporation or by reason of
the fact that such director or officer, at the request of the Corporation, is or
was serving any other corporation, partnership, joint 

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venture, employee benefit plan or other enterprise, in any capacity. Nothing
contained herein shall affect any rights to indemnification to which employees
other than directors or officers may be entitled by law. No amendment or repeal
of this Section A of Article XI shall apply to or have any effect on any right
to indemnification provided hereunder with respect to any acts or omissions
occurring prior to such amendment or repeal.

          B.    No director of the Corporation shall be personally liable to the
Corporation or its stockholders for monetary damages for any breach of fiduciary
duty by such a director as a director.  Notwithstanding the foregoing sentence,
a director shall be liable to the extent provided by applicable law (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 which involve intentional
misconduct or a knowing violation of law, (iii) pursuant to Section 174 of the
GCL, or (iv) for any transaction from which such director derived an improper
personal benefit.  No amendment to or repeal of this Section B of this Article
XI shall apply to or have any effect on the liability or alleged liability of
any director of the Corporation for or with respect to any acts or omissions of
such director occurring prior to such amendment or repeal.

          C.    In furtherance and not in limitation of the powers conferred by
statute:

          (i)   the Corporation may purchase and maintain insurance on behalf of
     any person who is or was a director, officer, employee or agent of the
     Corporation, or is serving at the request of the Corporation as a director,
     officer, employee or agent of another corporation, partnership, joint
     venture, trust, employee benefit plan or other enterprise against any
     liability asserted against him and incurred by him in any such capacity, or
     arising out of his status as such, whether or not the Corporation would
     have the power to indemnify him against such liability under the provisions
     of law; and

          (ii)  the Corporation may create a trust fund, grant a security
     interest and/or use other means (including, without limitation, letters of
     credit, surety bonds and/or other similar 

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     arrangements), as well as enter into contracts providing indemnification to
     the full extent authorized or permitted by law and including as part
     thereof provisions with respect to any or all of the foregoing to ensure
     the payment of such amounts as may become necessary to effect
     indemnification as provided therein, or elsewhere.

                                 ARTICLE XII.

          In furtherance and not in limitation of the powers conferred by
statute, the Board of Directors is expressly authorized to adopt, repeal, alter,
amend or rescind the Bylaws of the Corporation.  In addition, the Bylaws of the
Corporation may be adopted, repealed, altered, amended, or rescinded by the
affirmative vote of two-thirds of the issued and outstanding stock of the
Corporation entitled to vote thereon.

                                 ARTICLE XIII.

          The Corporation reserves the right to repeal, alter amend, or rescind
any provision contained in this Restated and Amended Certificate of
Incorporation, in the manner now or hereafter prescribed by statute, and all
rights conferred on stockholders herein are granted subject to this reservation.
Notwithstanding any other provision of this Restated and Amended Certificate of
Incorporation and any provisions of the Bylaws of the Corporation, any proposal
to amend or repeal Articles V, VI, VIII, IX, or XII, or this Article XIII or any
other proposal to amend this Restated and Amended Certificate of Incorporation
that is inconsistent with any provisions of Articles V, VI, VIII, IX, or XII or
this Article XIII shall require not less than the affirmative vote of two-thirds
of the issued and outstanding stock of the Corporation entitled to vote thereon.

                                 ARTICLE XIV.

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          The Corporation will not issue nonvoting equity securities to the
extent prohibited by Section 1123 of the United States Bankruptcy Code;
provided, however, that this Article XIV (a) will have no further force and
effect beyond that required under Section 1123 of the United States Bankruptcy
Code, (b) will have such force and effect, if any, only for so long as such
Section 1123 is in effect and applicable to the Corporation, and (c) in all
events may be amended or eliminated in accordance with applicable law as from
time to time in effect.

                               *   *   *   *   *

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