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                                                                   EXHIBIT 10.21



                              EMPLOYMENT AGREEMENT



                  THIS EMPLOYMENT AGREEMENT ("Agreement") is made as of this
15th day of May 1997 between ORBCOMM GLOBAL, L.P. (the "Company") and ROBERT F.
LATHAM (the "Executive").

                              W I T N E S S E T H:

                  WHEREAS, the Executive has heretofore for many years served in
an executive capacity with various entities and as a consequence thereof has
acquired significant management skills and experience; and

                  WHEREAS, the Company desires to employ the Executive as its
Executive Vice President and Chief Operating Officer for the term of employment
stated herein subject to the conditions hereof; and

                  WHEREAS, the Executive is willing and able to undertake
employment with the Company subject to the terms and conditions stated herein.

                  NOW, THEREFORE, the Company and the Executive each agree as
follows:

                  1. Employment; Duties. The Company hereby employs the
Executive and the Executive accepts employment as Executive Vice President and
Chief Operating Officer of the Company and President of ORBCOMM USA, L.P. In
such capacity, the Executive shall perform such executive duties and exercise
such powers for the Company and its subsidiaries (if any) as the General
Partners of the Company may assign to or vest in him from time to time
commensurate with his position as an Executive Vice President and Chief
Operating Officer of the Company and that until further notice by the General
Partners of the Company, such duties shall include management of the deployment
and operation of the Company's low-Earth orbit satellite communications system,
U.S. marketing and sales and financial operations and administration. During the
period of employment with the Company, the Executive will devote his best
efforts to the interest of the Company and will not engage in other employment
or in any activities detrimental to the best interests of the Company without
the prior written consent of the President and Chief Executive Officer of the
Company. The Company understands and agrees that, notwithstanding the foregoing,
and subject to Section 10(a), the Executive may serve during the term of this
Agreement as a director on the boards of directors of business, civic or
community corporations or entities other than the Company, if he shall obtain
the prior written approval of the Company's General Partners, which approval may
be withheld if the Company's General Partners reasonably determine that the
Executive's so serving as a director for any such
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corporation or entity would interfere with the performance of the Executive's
duties hereunder or would conflict with the best interests of the Company.

                  2. Term. This Agreement shall have a term of three years,
commencing on May 15, 1997 and ending on May 14, 2000, unless the term is
terminated earlier in accordance with this Agreement. This Agreement shall be
automatically extended from year to year thereafter for additional one year
periods under the same terms and conditions, unless either the Company or the
Executive notifies the other, in accordance with this Agreement, no later than
three months prior to the expiration of the then current term of this Agreement
of its intent to terminate this Agreement. On the expiration (but not
termination) of this Agreement at the end of term hereof, Executive shall be
eligible to become a Vice President, Special Projects and remain employed by the
Company, on terms and conditions to be mutually agreed to by the Company and
Executive, for a period of up to one year, provided that if Executive becomes
employed by another person or entity during such one year period, Executive
shall no longer be employed by the Company.

                  3. Compensation. During the term of this Agreement, the
Company shall pay to the Executive the following compensation:

                           (a) Base Salary. The Company shall pay to the
                  Executive compensation equal to an annual base salary at the
                  rate of one hundred eighty thousand dollars ($180,000) per
                  annum, prorated for any partial employment year, payable in
                  bi-weekly installments in arrears. During the term of this
                  Agreement, the Executive's compensation shall be reviewed by
                  the General Partners of the Company at least once every 12
                  months.

                           (b) Signing Bonus. The Company shall pay to the
                  Executive a signing bonus equal to $75,000, payable within
                  five business days of the date hereof, provided that, in the
                  event that within five years of the date hereof the Executive
                  receives any refunds or payments from any Country Club or
                  similar entity or transferee for membership dues repaid to the
                  Executive on the Executive's withdrawal from membership, the
                  Executive shall pay to the Company such refund up to $25,000.

                           (c) Bonus Plan. The Executive shall also participate
                  in the Company's Annual Incentive Bonus Plan (the "Bonus
                  Plan"), a copy of which is attached hereto as Attachment A,
                  provided that the Company, President and Chief Executive
                  Officer and the Executive agree to review and thereafter
                  revise the terms of the Bonus Plan by mutual agreement of the
                  Executive and the Company. For purposes of the Bonus Plan and
                  bonus amounts that may be payable to Executive for calendar
                  year 1997, Executive shall be deemed to have commenced
                  employment with the Company on January 1, 1997. From and after
                  the date hereof, the Executive shall be entitled to receive an
                  annual bonus of up to 50% (or any additional amount as may be
                  specified in the Bonus Plan as it may be modified as specified
                  herein or therein) of his annual base salary determined and


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                  payable in accordance with the terms and conditions of the
                  Bonus Plan as it may be modified as specified herein and
                  therein. The Executive and the Company shall mutually agree on
                  1997 Company and personal objectives as required by the Bonus
                  Plan.

                           (d) Stock Options. On the date hereof, the Executive
                  has been granted options (the "Options") to purchase 55,000
                  shares of the Common Stock, par value $.01 per share (the
                  "Common Stock"), of Orbital Communications Corporation
                  ("OCC"). Each Option shall be exercisable for one share of
                  Common Stock at an exercise price of $26.50 (subject to
                  adjustment for any stock split, reclassification or
                  recapitalization of the Common Stock) per share and shall
                  otherwise be governed by the terms of the Orbital
                  Communications Corporation 1992 Stock Option Plan (the "Option
                  Plan"), the form of stock option agreement, a copy of which is
                  attached hereto as Attachment B and, where applicable, this
                  Agreement. Subject to the terms of Sections 7 and 8, the
                  Options shall vest and be exercisable in equal one-quarter
                  increments as follows:

                               (i)   25% of the Options shall be vested on the
                                     date hereof;

                               (ii)  25% of the Options shall vest on the first
                                     anniversary of the date hereof;

                               (iii) 25% of the Options shall vest on the second
                                     anniversary of the date hereof; and

                               (iv)  25% of the Options shall vest on the third
                                     anniversary of the date hereof.

                  4. Other Compensation and Benefits. In addition to the
compensation specified in Section 3, the Company shall provide the following to
the Executive:

                           (a) Relocation. The Company shall pay the Executive's
                  actual and reasonable relocation expenses to the United States
                  as outlined in its Relocation Policy, as modified (the
                  "Relocation Policy"), a copy of which is attached hereto as
                  Attachment C, up to a maximum of $50,000; provided that
                  relocation expenses incurred to move the Executive from
                  England to the United States and reimbursed by the Executive's
                  last employer shall not be reimbursable by the Company. At the
                  termination of this Agreement or the Executive's death or
                  disability resulting in the termination of his employment, the
                  Company shall pay the Executive's or any surviving spouse's
                  actual and reasonable relocation expenses to Canada (of the
                  types specified in the Relocation Policy), up to a maximum of
                  $50,000.

                           (b) Bridge Loan. In addition, at the Executive's
                  request at any time during the first year of his employment
                  with the Company, the Company shall provide the Executive with
                  a bridge loan in the amount of up to $50,000 to assist in the
                  purchase of a home in the Washington area. The loan shall be
                  an interest

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                  free loan. The Loan shall be payable within one
                  year from the date made, provided that, if the Executive is
                  terminated without Cause (as defined in Section 9), the term
                  of the loan shall be extended one year.

                           (c) Legal Review of this Agreement. The Company shall
                  pay the Executive's actual legal expenses incurred in the
                  review of any offer letter previously provided by the Company
                  to the Executive and this Agreement, up to $2,000.

                           (d) Benefits. During the term of this Agreement, the
                  Executive shall be entitled to paid vacation and sick leave as
                  made generally available to the senior executives of the
                  Company, and to participate in any profit sharing plan,
                  retirement plan, group life insurance plan or other insurance
                  plan or medical expense plan maintained by the Company for its
                  senior executives generally and, if applicable, their family
                  members. The Company reserves the right to discontinue or to
                  amend such plans to conform to legal requirements or for other
                  reasons, as determined by the Company to be in the best
                  interest of the business.

                           (e) Directors and Officers Insurance. The Company
                  shall use all commercially reasonable efforts to maintain
                  Directors and Officers Insurance covering such claims and in
                  such amounts as the Company shall determine to be appropriate.

                  5. Business Expenses; Professional Memberships. The Company
shall reimburse the Executive for all reasonable and necessary (a) business
expenses, including, but not limited to, travel expenses and telephone usage
charges incurred by him in the performance of his duties under this Agreement,
and (b) professional membership dues, against presentation of proper receipts or
other proof of expenditure, and subject to such reasonable guidelines or
limitations provided to the Executive, and which are to be applied prospectively
only as the General Partners or the Chief Executive Officer of the Company may
impose. Executive shall be furnished with a portable computer and two
appropriate docking stations one for use in his office and one for use in his
home, as well as a printer for use in his home.

                  6. Termination on Death or Disability. This Agreement shall
automatically terminate on the death or disability of the Executive. The
Executive shall be deemed to be disabled if the General Partners of the Company
shall determine that the Executive is unable to perform substantially all of his
duties under this Agreement for a continuous period in excess of ninety (90)
days because of a disabling illness or injury. During any disability period, the
Executive shall be entitled to compensation as specified in any relevant written
employment/benefit policies and procedures of the Company as may be in effect
from time to time.

                  7. Change of Control. In the event a person other than OCC or
Teleglobe Mobile Partners owns a majority of the general partnership interests
(or other similar equity interests) of the Company (a "Change of Control"), the
Executive shall have the option,

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exercisable within three months of the Change of Control, to terminate his
employment with the Company and receive the following benefits:

                           (a) Within 30 days of the exercise of such option by
                  the Executive, payment of (i) the remaining balance of the
                  Executive's base salary through the end of the term of this
                  Agreement plus (ii) an amount equal to 50% of the Executive's
                  then current annual base salary;

                           (b) Automatic vesting of all unvested Options; and

                           (c) Payment of the Executive's actual and reasonable
                  expenses to relocate to Canada (of the types specified in the
                  Relocation Policy), up to a maximum of $50,000.

                  8. Termination Without Cause. During the term of this
Agreement, the Company shall be entitled to terminate the Executive without
Cause, provided that if the Executive is terminated without Cause, the Executive
shall be entitled to receive the following benefits:

                           (a) A lump sum amount equal to 12 months annual base
                  salary, payable within 30 days of such termination;

                           (b) The vesting schedule for the Options shall be
                  revised for unvested options such that, vesting of the next
                  annual installment (e.g. 12,500) would occur in equal quarters
                  amounts (e.g. 3,125) for each full calendar quarter the
                  Executive was employed by the Company (from the last annual
                  vesting date) prior to the Executive's termination. In
                  addition, on the exercise of any vested options, payment of
                  any withholding taxes then due could be made by (i)
                  surrendering Common Stock held by the Executive having a fair
                  market value equal to such withholding tax obligation or (ii)
                  requesting that OCC withhold from the shares to be delivered
                  to the Executive on the exercise of vested Options a number of
                  shares of Common Stock having a fair market value equal to
                  such withholding tax obligation; and

                           (c) Payment of the Executive's actual and reasonable
                  expenses to relocate to Canada (of the types specified in the
                  Relocation Policy), up to a maximum of $50,000.

                  9. Termination For Cause or on Death. Notwithstanding any
other provision of this Agreement, the employment of the Executive and this
Agreement may be terminated by the Company on the death of the Executive or for
Cause. Termination for Cause shall be effective as of the date the Company gives
notice to the Executive in accordance with this Agreement. Termination for Cause
shall be limited to the following acts by, or conditions with respect to, the
Executive, as shall be determined by the General Partners acting in their
reasonable discretion:


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                           (a) chronic alcoholism;

                           (b) drug addiction;

                           (c) the Executive's (i) conviction for a felony or
                  any crime involving moral turpitude, fraud, or
                  misrepresentation or (ii) misappropriation or embezzlement of
                  funds or assets from the Company;

                           (d) any intentional act having the purpose and effect
                  of materially injuring the reputation, business or business
                  relationships of the Company;

                           (e) any breach by the Executive of the provisions of
                  this Agreement, including, without limitation, the agreements
                  contained in Sections 10(a) and (b) hereof; or

                           (f) committing acts amounting to gross negligence or
                  willful misconduct to the detriment of the Company or its
                  affiliates.

                  10.      Company Matters.

                           (a) Proprietary Information and Inventions.
                  Concurrently with the execution of this Agreement, the
                  Executive has executed an Employee Non-Disclosure Agreement, a
                  copy of which is attached hereto as Attachment D. The
                  Executive agrees to abide by the terms and conditions set
                  forth therein.

                           (b) Non-Solicitation of Employees. The Executive
                  agrees that, during the term of his employment and for a
                  period of one year thereafter, he will not solicit or
                  encourage any employee of the Company to terminate his or her
                  employment with the Company or to accept employment with any
                  other employer with whom the Executive might become affiliated
                  subsequent to his termination.

                           (c) Resignation on Termination. On termination of his
                  employment, the Executive shall immediately resign any
                  directorships, offices or other positions that he may hold in
                  the Company or any of its affiliates.

                  11.      Miscellaneous.

                           (a) Work Authorization. The Company shall be
                  responsible for obtaining all appropriate work authorization
                  papers necessary for the Executive to be employed by the
                  Company during the term of this Agreement.

                           (b) Entire Agreement; Binding Effect. This Agreement
                  sets forth the entire understanding between the parties as to
                  the subject matter of this Agreement and merges and supersedes
                  all prior agreements, commitments, representations, writings
                  and discussions between them; and neither of the parties shall
                  be bound by any obligations, conditions, warranties or
                  representations with


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                  respect to the subject matter of this Agreement, other than as
                  expressly provided in this Agreement or as duly set forth on
                  or subsequent to the date hereof in writing and signed by the
                  proper and duly authorized representative of the party to be
                  bound hereby. This Agreement is binding on the Executive and
                  on the Company and its successors and assigns (whether by
                  assignment, by operation of law or otherwise).

                           (c) Notices. All notices, approvals, consents,
                  requests or demands required or permitted to be given under
                  this Agreement shall be in writing and shall be deemed
                  sufficiently given three business days after being deposited
                  in the mail, registered or certified, postage prepaid, on
                  receipt if hand delivered or sent by facsimile (answerback
                  received) or one business day after being given to a reputable
                  overnight courier and addressed to the party entitled to
                  receive such notice at the following address (or other such
                  addresses as the parties may subsequently designate):

                           The Company:     ORBCOMM Global, L.P.
                                            21700 Atlantic Boulevard
                                            Dulles, Virginia  20166

                           The Executive:   2121 Wilkes Ct.
                                            Herndon, Virginia



         If notice is given by any other method, it shall be deemed effective
when the written notice is actually received.

                           (d) Waivers. No party shall be deemed to have waived
                  any right, power or privilege under this Agreement or any
                  provisions hereof unless such waiver shall have been duly
                  executed in writing and acknowledged by the party to be
                  charged with such waiver. The failure of any party at any time
                  to insist on performance of any of the provisions of this
                  Agreement shall in no way be construed to be a waiver of such
                  provisions, nor in any way to affect the validity of this
                  Agreement or any part hereof. No waiver of any breach of this
                  Agreement shall be held to be a waiver of any other subsequent
                  breach.

                           (e) Governing Law; Jurisdiction. This Agreement shall
                  be governed by, and construed and enforced in accordance with,
                  the laws of the Commonwealth of Virginia, without giving
                  effect to the conflict or choice of law provisions thereof. In
                  addition, each party hereto irrevocably and unconditionally
                  agrees that any suit, action or other legal proceeding arising
                  out of this Agreement may be brought only in the Commonwealth
                  of Virginia.


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                  IN WITNESS WHEREOF, this parties hereto have executed this
Agreement as of the day and year first written above.





                                              ORBCOMM Global, L.P.


                                              By: ______________________________
                                                       Name:  Alan L. Parker
                                                       Title:  President


                                              __________________________________
                                              Robert F. Latham


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                              ORBCOMM GLOBAL, L.P.

                            NON-DISCLOSURE AGREEMENT

                  This Non-Disclosure Agreement (the "Agreement") is made and
entered into this 7th day of April, 1997 by and between ORBCOMM Global, L.P.
("ORBCOMM"), a Delaware corporation, with its principal place of business
located at 21700 Atlantic Boulevard, Dulles, Virginia 20166, and Robert F.
Latham ("Latham").

                  WHEREAS, Latham will provide consulting services to ORBCOMM
and in connection therewith will receive ORBCOMM proprietary or confidential
information;

                  NOW, THEREFORE, the parties hereto agree as follows:

                  1. PROPRIETARY INFORMATION. For purposes of this Agreement,
"ORBCOMM Proprietary Information" shall mean written, documentary or oral
information of any kind, including, but not limited to, (a) information of a
business, planning, marketing or technical nature, (b) models, tools, hardware
and software disclosed by ORBCOMM to Latham or generated by Latham in the course
of performing work under this Agreement, and (c) any documents, reports,
memoranda, notes, files or analyses that contain, summarize or are based upon
any of the foregoing. With respect to ORBCOMM Global, "Proprietary Information"
shall include any of the foregoing information of any of ORBCOMM USA, L.P. or
ORBCOMM INTERNATIONAL PARTNERS, L.P. Proprietary Information" shall not include
information that:

                               (i)   is publicly available prior to the date of
                                     this Agreement;

                               (ii)  becomes publicly available after the date
                                     of this Agreement through no wrongful act
                                     of Latham;

                               (iii) is furnished to others by ORBCOMM without
                                     similar restrictions on their right to use
                                     or disclose;

                               (iv)  is known by Latham without any proprietary
                                     restrictions at the time of receipt of such
                                     information from ORBCOMM or becomes
                                     rightfully known to Latham without
                                     proprietary restrictions from a source
                                     other than ORBCOMM;

                               (v)   is independently developed by Latham by
                                     persons who did not have access, directly
                                     or indirectly, to the Proprietary
                                     Information; or

                               (vi)  is obligated to be produced under order of
                                     a court of competent jurisdiction or a
                                     valid administrative or congressional
                                     subpoena, provided that Latham promptly
                                     notifies ORBCOMM of such event so that
                                     ORBCOMM


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                                     may seek an appropriate protective
                                     order or waive compliance by Latham with
                                     the terms of this Agreement.

                  2. CONFIDENTIALITY.

                           a. Latham shall protect all ORBCOMM Proprietary
Information as confidential information and, except with the prior written
consent of ORBCOMM or as otherwise specifically provided herein, shall not
disclose, copy or distribute the ORBCOMM Proprietary Information to any other
individual, corporation or entity for a period of three (3) years from the date
of disclosure by ORBCOMM or creation by Latham.

                           b. Latham shall not make any use of the ORBCOMM
Proprietary Information for his or her own benefit or for the benefit of any
other individual, corporation or entity.

                           c. Latham shall not disclose all or any part of the
ORBCOMM Proprietary Information to his or her affiliates, agents or
representatives (collectively, "Representatives") except on a need-to-know
basis. Latham agrees to inform any of his or her Representatives who receive
ORBCOMM Proprietary Information of the confidential and proprietary nature
thereof and of such Representative's obligations with respect to the maintenance
of the ORBCOMM Proprietary Information in conformance with the terms of this
Agreement.

                           d. Latham shall maintain the ORBCOMM Proprietary
Information with at least the same degree of care Latham uses to maintain his or
her own proprietary information. Latham represents that such degree of care
provides adequate protection for his or her own proprietary information.

                           e. Latham shall immediately advise ORBCOMM in writing
of any misappropriation or misuse by any person of the ORBCOMM Proprietary
Information of which Latham is aware.

                           f. Any documents or materials that are furnished by
or on behalf of ORBCOMM, and all other ORBCOMM Proprietary Information in
whatever form, including documents, reports, memoranda, notes, files or analyses
prepared by or on behalf of Latham, including all copies of such materials,
shall be promptly returned by Latham to ORBCOMM upon written request by ORBCOMM
for any reason.

                  3. NO LICENSES OR WARRANTIES. No license to Latham under any
trade secrets or patents is granted or implied by conveying ORBCOMM Proprietary
Information or other information to Latham; and none of the information
transmitted or exchanged by ORBCOMM shall constitute any representation,
warranty, assurance, guaranty or inducement by ORBCOMM to Latham with respect to
the infringement of patents or other rights of others.

                  4. REMEDY FOR BREACH. Latham acknowledges that the ORBCOMM
Proprietary Information is central to ORBCOMM's business and was developed by or
for

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ORBCOMM at a significant cost. Latham further acknowledges that damages
would not be an adequate remedy for any breach of this Agreement by Latham or
his or her Representatives and that ORBCOMM may obtain injunctive or other
equitable relief to remedy or prevent any breach or threatened breach of this
Agreement by Latham or any of his or her Representatives. Such remedy shall not
be deemed to be the exclusive remedy for any such breach of this Agreement, but
shall be in addition to all other remedies available at law or in equity to
ORBCOMM.

                  5. MISCELLANEOUS.

                           a. This Agreement contains the entire understanding
between Latham and ORBCOMM and supersedes all prior written and oral
understandings relating to the subject hereof. This Agreement may not be
modified except by a writing signed by both parties.

                           b. The construction, interpretation and performance
of this Agreement, as well as the legal relations of the parties arising
hereunder, will be governed by and construed in accordance with the laws of the
Commonwealth of Virginia, without regard to the choice or conflict of law
provisions thereof.

                           c. It is understood and agreed that no failure or
delay by ORBCOMM in exercising any right, power or privilege hereunder shall
operate as a waiver thereof, nor shall any single or partial exercise thereof
preclude any other or further exercise thereof, or the exercise of any other
right, power or privilege hereunder. No waiver of any terms or conditions of
this Agreement shall be deemed to be a waiver of any subsequent breach of any
term or condition. All waivers must be in writing and signed by the party sought
to be bound.

                           d. If any part of this Agreement shall be held
unenforceable, the remainder of this Agreement will, nevertheless, remain in
full force and effect.

                  IN WITNESS WHEREOF, each of the parties of this Agreement has
caused this Agreement to be signed as of the day and year first above written.



ORBCOMM GLOBAL, L.P.



By: ______________________________                  ____________________________
    Mary Ellen Seravalli                            Robert F. Latham
    Senior Vice President and General Counsel


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