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                                                                Exhibit 10(dd)

                                                   December 20, 1999



THIS LETTER CONSTITUTES PART OF A PROSPECTUS
COVERING SECURITIES THAT HAVE BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED

   RE:  Lockheed Martin Corporation 1995 Omnibus Performance Award Plan ("Plan")

Dear Optionee:

   Effective December 2, 1999, the Stock Option Subcommittee of the Board of
Directors of Lockheed Martin Corporation (the "Corporation") has amended the
terms of your outstanding Lockheed Martin stock options previously granted under
the referenced Plan.  The amendments provide that:

 .  If you die, the expiration date of your outstanding options will be
   unaffected and will expire at the end of their remaining term. This amends
   the duration of the exercise period for your beneficiaries from three years
   following your death to the end of your options' remaining term.

 .  If you are divested from the Corporation as defined in your outstanding Plan
   award agreements, the vesting schedule of your outstanding options will be
   unaffected by the divestiture and your outstanding options will expire on the
   fifth anniversary of the effective date of the divestiture, or the original
   expiration date, whichever occurs first. This amends the duration of the
   exercise period following divestiture from one year to five years (but in no
   case longer than the original term), and provides for continued vesting of
   your options following divestiture (previously, unvested options at the time
   of the divestiture were forfeited). The provision concerning your rights upon
   voluntary or involuntary termination (other than layoff) has also been
   amended but the amendments are technical and do not change the meaning of the
   provision.

The full text of the amendments (including non-substantive technical changes) as
implemented in the award letters previously issued to you follow:

     SPECIAL RULES AS TO EXPIRATION AND FORFEITURE

       Death - Options will expire at the end of their remaining term.

       Resignation, Lay-Off or Termination for Cause - If you resign or
     otherwise terminate, whether voluntarily or by action of the Corporation
     and in the latter case
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     whether with or without "cause," unvested Options will be forfeited upon
     your termination. Vested Options will expire at the end of their remaining
     term or 186 calendar days following your resignation or termination,
     whichever is shorter. If you are laid off, your options will be unaffected,
     and will vest and be exercisable until the end of their remaining term, in
     accordance with the terms of the Plan.

       Divestiture - If the Corporation divests (as defined below) all or
     substantially all of a business operation of the Corporation and such
     divestiture results in the termination of the recipient's employment with
     the Corporation or its subsidiaries and transfer of such employment to the
     other party to the divestiture, the special rules in this paragraph will
     apply.  Your service with the other party to the divestiture will be
     treated as service with the Corporation and you will continue to vest in
     your unvested options while employed by that party as though you had
     remained in the employ of the Corporation.  Following a divestiture, your
     vested options will be exercisable until the first to occur of (i) the
     fifth anniversary of the effective date of the divestiture; or (ii) the
     original expiration date ("Divestiture Expiration Date").  If you die
     following divestiture but prior to the Divestiture Expiration Date, all
     unvested options will immediately vest as of the date of death and be
     exercisable by your beneficiary until the Divestiture Expiration Date.  For
     the purposes of this provision, the term "divestiture" shall mean a
     transaction which results in the transfer of control of the business
     operation divested to any person, corporation, association, partnership,
     joint venture or other business entity of which less than 50% of the voting
     stock or other equity interests (in the case of entities other than
     corporations), is owned or controlled directly or indirectly, by the
     Corporation, one or more of the Corporation's subsidiaries or by a
     combination thereof.

   This letter is intended to notify each holder of options under the Plan that
the amendments have been fully implemented on a prospective basis as of December
2, 1999 and will apply to divestitures and deaths occurring after that date.
Except for the amendments, which serve as an extension of the exercise periods
under circumstances of divestiture or death from those previously authorized,
each option remains in full force and effect in accordance with its terms in
effect prior to the amendments.  The amendments do not apply at this time to
Section 16 Insiders.

   If you have questions regarding the amendments, please address them to ____,
or me.

                                                Very truly yours,


                                                /s/ Lillian M. Trippett