Exhibit 99 Text of registrant's press release dated December 16, 1999 -

For Immediate Release
                                     Contact:  Thomas L. Langford
                                               Executive Vice President
                                               (617) 589-7424


             STONE & WEBSTER SELLS STOCK TO EMPLOYEE RETIREMENT PLAN

     Boston,  Massachusetts,  December 16, 1999 - Stone & Webster,  Incorporated
announced  today that it sold one  million  shares of its Common  Stock from its
treasury to the Employee  Retirement Plan of Stone & Webster,  Incorporated  and
Participating  Subsidiaries (the "Retirement  Plan").  The purchase price, which
was based on recent market prices for the Common Stock and discounted to reflect
a block  transaction,  was  determined  to be fair to the  Retirement  Plan in a
fairness  opinion  delivered  to the Trustee  under the  Retirement  Plan by the
independent firm of Houlihan Lokey Howard & Zukin Financial Advisors, Inc.

     The Board of Directors of the Company had previously authorized the Trustee
to make purchases of Common Stock in market transactions, and between August and
October,  1999,  the  Retirement  Plan had acquired a total of 79,800  shares in
purchases  made on the market.  At its meeting on December 14,  1999,  the Board
determined  that  this  sale of Common  Stock  was in the  interest  of both the
Company's shareholders and the Retirement Plan.

     As a result of this transaction, Stone & Webster, Incorporated will receive
in excess of $15 million in new capital, which it will use for general corporate
purposes.

     Stone & Webster has recently  completed its FY2000  Operating  Plan and its
Board of  Directors  reviewed and approved the Plan in concert with its decision
to release  the  additional  shares.  The  Company's  management  believes  that
operating  results for FY2000 will meet current analyst  expectations  after the
dilution resulting from the additional shares.

     Stone &  Webster  is a  global  leader  in  engineering,  construction  and
consulting  services  for  power,  process,  environmental,  infrastructure  and
industrial markets.

     Safe Harbor statement under the Private Securities Litigation Reform Act of
1995: Any forward-looking statements made in this release represent management's
best  judgment as to what may occur in the future.  The Company  cautions that a
variety of  factors,  including  but not limited to the  following,  could cause
business  conditions and results to differ  materially from what is contained in
forward-looking statements: changes in the rate of economic growth in the United
States and other major  international  economies,  changes in  investment by the
energy, power and environmental  industries,  the uncertain timing of awards and
contracts,  changes in  regulatory  environment,  changes in project  schedules,
changes  in  trade,   monetary   and  fiscal   policies   world-wide,   currency
fluctuations, outcomes of pending and future litigation, protection and validity
of patents and other  intellectual  property rights,  increasing  competition by
foreign and domestic companies and other risks detailed from time to time in the
Company's  filings  with the  Securities  and Exchange  Commission.  The Company
undertakes   no   obligation   to  publicly   release  any   revisions   to  the
forward-looking  statements or reflect events or circumstances after the date of
this document.

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