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                                                                  Exhibit 10.13


                         ARCH COMMUNICATIONS GROUP, INC.

                             1997 STOCK OPTION PLAN

     Adopted by the Board of Directors on February 10, 1997

1. Purpose

     The purpose of this 1997 Stock Option Plan (the "Plan") of Arch
Communications Group, Inc., a Delaware corporation (the "Company"), is to
advance the interests of the Company's stockholders by enhancing the Company's
ability to attract, retain and motivate persons who make (or are expected to
make) important contributions to the Company by providing such persons with
equity ownership opportunities and incentives in order to better align the
interests of such persons with those of the Company's stockholders. Except where
the context otherwise requires, the term "Company" shall include any present or
future subsidiary corporations of Arch Communications Group, Inc. as defined in
Section 424(f) of the Internal Revenue Code of 1986, as amended, and any
regulations promulgated thereunder (the "Code").

2. Eligibility

     All of the Company's employees, officers, directors, consultants and
advisors are eligible to be granted options ("Options") under the Plan. Any
person who has been granted an Option under the Plan shall be deemed a
"Participant".

3. Administration, Delegation

     (a) Administration by Board of Directors. The Plan will be administered by
the Board of Directors of the Company (the "Board"). The Board shall have
authority to grant Options and to adopt, amend and repeal such administrative
rules, guidelines and practices relating to the Plan as it shall deem advisable
from time to time to interpret and correct the provisions of the Plan and any
Option. No member of the Board shall be liable for any action or determination
relating to the Plan. All decisions by the Board shall be made in the sole
discretion of the Board and shall be final and binding on all persons having or
claiming any interest in the Plan or in any Option.

     (b) Delegation to Executive Officers. To the extent permitted by applicable
law, the Board may delegate to one or more executive officers of the Company the
power to grant Options and exercise such other powers under the Plan as the
Board may determine, provided that the Board shall fix the maximum number of
shares subject to Options and the maximum number of shares for any one
Participant to be made by such executive officers.

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     (c) Appointment of Committees. To the extent permitted by applicable law,
the Board may delegate any or all of its powers under the Plan to one or more
committees or subcommittees of the Board (a "Committee"). All references in the
Plan to the "Board" shall mean a Committee or the Board or the executive officer
referred to in Section 3(b) to the extent of such delegation.

4. Stock Available for Options

     (a) Number of Shares. Subject to adjustment under Section 4(c), Options may
be granted under the Plan for up to 1,500,000 shares of common stock, $.01 par
value per share, of the Company (the "Common Stock"). If any Option expires or
is terminated, surrendered or canceled without having been fully exercised, the
unused Common Stock covered by such Option shall again be available for the
grant of Options under the Plan, subject, however, in the case of Incentive
Stock Options (as defined hereinafter) to any limitation required under the
Code. Shares issued under the Plan may consist in whole or in part of authorized
but unissued shares or treasury shares.

     (b) Per-Participant Limit. Subject to adjustment under Section 4(c), the
maximum number of shares with respect to which an Option may be granted to any
Participant under the Plan shall be 200,000 shares per calendar year. The
per-Participant limit described in this Section 4(b) shall be construed and
applied consistently with Section 162(m) of the Code.

     (c) Adjustment to Common Stock. In the event of any stock split, stock
dividend, recapitalization, reorganization, merger, consolidation, combination,
exchange of shares, liquidation, spin-off or other similar change in
capitalization or event, or any distribution to holders of Common Stock other
than a normal cash dividend, (i) the number and class of securities available
under this Plan and (ii) the number and class of security and exercise price per
share subject to each outstanding Option shall be appropriately adjusted by the
Company (or substituted Options may be granted, if applicable) to the extent the
Board shall determine, in good faith, that such an adjustment (or substitution)
is necessary and appropriate. If this Section 4(c) applies and Section 6(e)(1)
also applies to any event, Section 6(e)(1) shall be applicable to such event,
and this Section 4(c) shall not be applicable to such event.

5. Stock Options

     (a) General. The Board may grant Options to purchase Common Stock and
determine the number of shares of Common Stock to be covered by each Option, the
exercise price of each Option and the conditions and limitations applicable to
the exercise of each Option, including conditions relating to applicable federal
or state securities laws, as it considers necessary or advisable. An


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Option which is not intended to be an Incentive Stock Option (as hereinafter
defined) shall be designated a "Nonstatutory Stock Option".

     (b) Incentive Stock Options. An Option that the Board intends to be an
"incentive stock option" as defined in Section 422 of the Code (an "Incentive
Stock Option") shall only be granted to employees of the Company and shall be
subject to and shall be construed consistently with the requirements of Section
422 of the Code. The Company shall have no liability to a Participant, or any
other party, if an Option (or any part thereof) which is intended to be an
Incentive Stock Option is not an Incentive Stock Option.

     (c) Exercise Price. The Board shall establish the exercise price at the
time each Option is granted; provided, however, that in no event shall Options
be granted with an exercise price below the fair market value of the Common
Stock at the date of grant ("Fair Market Value") as determined by the Board in
good faith.

     (d) Duration of Options. Each Option shall be exercisable at such times and
subject to such terms and conditions as the Board may specify.

     (e) Exercise of Option. Options may be exercised only by delivery to the
Company of a written notice of exercise signed by the proper person together
with payment in full as specified in Section 5(f) for the number of shares for
which the Option is exercised.

     (f) Payment Upon Exercise. Common Stock purchased upon the exercise of an
Option granted under the Plan shall be paid for as follows:

          (i) in cash or by check, payable to the order of the Company;

          (ii) except as the Board may otherwise provide with respect to an
Option, delivery of an irrevocable and unconditional undertaking by a
creditworthy broker to deliver promptly to the Company sufficient funds (in cash
or by check) to pay the exercise price, or delivery by the Participant to the
Company of a copy of irrevocable and unconditional instructions to a
creditworthy broker to deliver promptly to the Company sufficient funds (in cash
or by check) to pay the exercise price;

          (iii) to the extent permitted by the Board and explicitly provided in
the agreement evidencing the Option (i) by delivery of shares of Common Stock
owned by the Participant valued at their fair market value as determined by the
Board in good faith ("Fair Market Value"), which Common Stock was owned by the
Participant at least six months prior to such delivery, (ii) by


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delivery of a promissory note of the Participant to the Company on terms
determined by the Board, or (iii) by payment of such other lawful consideration
as the Board may determine; or

          (iv) any combination of the above permitted forms of payment.

6. General Provisions Applicable to Options

     (a) Transferability of Options. Except as the Board may otherwise determine
or provide with respect to an Option, Options shall not be sold, assigned,
transferred, pledged or otherwise encumbered by the person to whom they are
granted, either voluntarily or by operation of law, except by will or the laws
of descent and distribution, and, during the life of the Participant, shall be
exercisable only by the Participant. References to Participant, to the extent
relevant in the context, shall include references to authorized transferees.

     (b) Documentation. Each Option under the Plan shall be evidenced by a
written instrument in such form as the Board shall determine. Each Option may
contain terms and conditions in addition to those set forth in the Plan.

     (c) Board Discretion. The terms of each Option need not be identical, and
the Board need not treat Participants uniformly.

     (d) Termination of Status. The Board shall determine the effect on an
Option of the disability, death, retirement, authorized leave of absence or
other change in the employment or other status of a Participant and the extent
to which, and the period during which, the Participant, the Participant's legal
representative, conservator, guardian or the beneficiary designated by a
Participant in the event of the Participant's death (the "Designated
Beneficiary"). In the absence of an effective designation by a Participant,
Designated Beneficiary shall mean the Participant's estate.

     (e) Acquisition Events.

          (i) Consequences of Acquisition Events. Upon the occurrence of an
Acquisition Event (as defined below), or the execution by the Company of any
agreement with respect to an Acquisition Event, the Board shall provide written
notice to the Participants that all Options then outstanding shall become
immediately exercisable in full as of a specified date (the "Acceleration Date")
prior to the Acquisition Event and will terminate immediately prior to the
consummation of such Acquisition Event, except to the extent exercised by the
Participants between the Acceleration Date and the consummation of such
Acquisition Event. An "Acquisition Event" shall mean: (a) any merger or
consolidation which results in the voting securities


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of the Company outstanding immediately prior thereto continuing to represent
(either by remaining outstanding or by being converted into voting securities of
the surviving or acquiring entity) less than 50% of the combined voting power of
the voting securities of the Company or such surviving or acquiring entity
outstanding immediately after such merger or consolidation; (b) any sale of all
or substantially all of the assets of the Company; (c) the complete liquidation
of the Company; or (d) the acquisition of "beneficial ownership" (as defined in
Rule 13d-3 under the Securities Exchange Act of 1934, as amended (the "Exchange
Act")) of securities of the Company representing 50% or more of the combined
voting power of the Company's then outstanding securities (other than through a
merger or consolidation or an acquisition of securities directly from the
Company) by any "person", as such term is used in Sections 13(d) and 14(d) of
the Exchange Act other than the Company, any trustee or other fiduciary holding
securities under an employee benefit plan of the Company, or any corporation
owned directly or indirectly by the stockholders of the Company in substantially
the same proportion as their ownership of stock of the Company.

          (ii) Assumption of Options Upon Certain Events. The Board may grant
Options under the Plan in substitution for options and other stock-based awards
held by employees of another corporation who become employees of the Company as
a result of a merger or consolidation of the employing corporation with the
Company or the acquisition by the Company of property or stock of the employing
corporation. The substitute Options shall be granted on such terms and
conditions as the Board considers appropriate in the circumstances.

     (f) Withholding. Each Participant shall pay to the Company, or make
provision satisfactory to the Company for payment of, any taxes required by law
to be withheld in connection with such Participant's Option no later than the
date of the event creating the tax liability. The Board may allow Participants
to satisfy such tax obligations in whole or in part in shares of Common Stock,
including shares retained from the Option creating the tax obligation, valued at
their Fair Market Value. The Company may, to the extent permitted by law, deduct
any such tax obligations from any payment of any kind otherwise due to a
Participant.

     (g) Amendment of Option. The Board may amend, modify or terminate any
outstanding Option, including but not limited to substituting therefor another
Option, changing the date of exercise or converting an Incentive Stock Option to
a Nonstatutory Stock Option, provided that the Participant's consent to such
action shall be required unless the Board determines that the action, taking
into account any related action, would not materially and adversely affect the
Participant.

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     (h) Conditions on Delivery of Stock. The Company will not be obligated to
deliver any shares of Common Stock pursuant to the Plan until (i) all conditions
of the Option have been met or removed to the satisfaction of the Company, (ii)
in the opinion of the Company's counsel, all other legal matters in connection
with the issuance and delivery of such shares have been satisfied, including any
applicable securities laws and any applicable stock exchange or stock market
rules and regulations, and (iii) the Participant has executed and delivered to
the Company such representations or agreements as the Company may consider
appropriate to satisfy the requirements of any applicable laws, rules or
regulations.

7. Miscellaneous

     (a) No Right To Employment or Other Status. No person shall have any claim
or right to be granted an Option, and the grant of an Option shall not be
construed as giving a Participant the right to continued employment or any other
relationship with the Company. The Company expressly reserves the right at any
time to dismiss or otherwise terminate its relationship with a Participant free
from any liability or claim under the Plan, except as expressly provided in the
applicable Option agreement.

     (b) No Rights As Stockholder. Subject to the provisions of the applicable
Option agreement, no Participant or Designated Beneficiary shall have any rights
as a stockholder with respect to any shares of Common Stock issuable upon
exercise of an Option until becoming the record holder thereof.

     (c) Effective Date and Term of Plan. The Plan shall become effective on the
date on which it is adopted by the Board, but no Option granted to a Participant
designated as subject to Section 162(m) by the Board shall become exercisable
unless and until the Plan has been approved by the Company's stockholders. No
Options shall be granted under the Plan after the completion of ten years from
the earlier of (i) the date on which the Plan was adopted by the Board or (ii)
the date the Plan was approved by the Company's stockholders, but Options
previously granted may extend beyond that date.

     (d) Amendment of Plan. The Board may amend, suspend or terminate the Plan
or any portion thereof at any time, provided that no Option granted to a
Participant designated as subject to Section 162(m) by the Board after the date
of such amendment shall become exercisable, to the extent that such amendment to
the Plan was required to grant such Option to a particular Participant, unless
and until such amendment shall have been approved by the Company's stockholders.



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     (e) Stockholder Approval. For purposes of this Plan, stockholder approval
shall mean approval by a vote of the stockholders in accordance with the
requirements of Section 162(m) of the Code.

     (f) Governing Law. The provisions of the Plan and all Options granted
hereunder shall be governed by and interpreted in accordance with the laws of
the State of Delaware, without regard to any applicable conflicts of law.





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