Exhibit 10.12


                         ARCH COMMUNICATIONS GROUP, INC.

                        1999 EMPLOYEE STOCK PURCHASE PLAN

                                January 26, 1999


The purpose of this Plan is to provide eligible employees of Arch Communications
Group, Inc. (the "Company") and certain of its subsidiaries  with  opportunities
to purchase  shares of the Company's  common stock,  $.01 par value (the "Common
Stock"), commencing either (i) promptly after the Special Meeting approving this
Plan if such  commencement  date is on or before  March 31, 1999 or (ii) July 1,
1999. One Million Five Hundred  Thousand  (1,500,000)  shares of Common Stock in
the aggregate have been approved for this purpose.

   1.  Administration.  The Plan will be  administered by the Company's Board of
Directors  (the  "Board")  or by the  Executive  Compensation  and Stock  Option
Committee  of the  Board  (the  "Committee").  The  Board or the  Committee  has
authority to make rules and regulations for the  administration  of the Plan and
its  interpretation  and  decisions  with  regard  thereto  shall be  final  and
conclusive.

   2.  Eligibility.  Participation  in the Plan will  neither be  permitted  nor
denied contrary to the  requirements of Section 423 of the Internal Revenue Code
of 1986, as amended (the "Code"), and regulations  promulgated  thereunder.  All
employees  of the  Company,  including  Directors  who  are  employees,  and all
employees of any  subsidiary of the Company (as defined in Section 424(f) of the
Code) at the  time  this  Plan is  adopted  and any  future  subsidiary  if such
subsidiary is specifically  included by the Board or the Committee (an "Eligible
Subsidiary"), are eligible to participate in any one or more of the offerings of
Options  (as  defined in  Section 9) to  purchase  Common  Stock  under the Plan
provided that:

      (a) they are customarily employed by the Company or an Eligible Subsidiary
   for more  than 20 hours a week and for more than  five  months in a  calendar
   year; and

      (b) they have been employed by the Company or an Eligible  Subsidiary  for
   at least three months prior to enrolling in the Plan; and

      (c) they are  employees  of the Company or an Eligible  Subsidiary  on the
   first day of the applicable Plan Period (as defined below).

No employee  may be granted an option  hereunder if such  employee,  immediately
after the option is granted,  owns 5% or more of the total combined voting power
or value of the stock of the  Company or any  subsidiary.  For  purposes  of the
preceding  sentence,  the attribution  rules of Section 424(d) of the Code shall
apply in determining the stock ownership of an employee, and all stock which the
employee has a contractual  right to purchase shall be treated as stock owned by
the employee.

   3. Offerings.  The Company will make one or more offerings  ("Offerings")  to
employees to purchase  stock under this Plan.  The first  Offering will commence
either (i) promptly after the Special Meeting approving the Plan and run through
June 30, 1999 if such



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commencement  date is on or before  March 31,  1999 or (ii) July 1, 1999 and run
through  December 31, 1999.  Subsequent  Offerings will begin each January 1 and
July 1,  or the  first  business  day  thereafter  (the  "Offering  Commencement
Dates").  Each Offering Commencement Date will begin a six-month period (a "Plan
Period") during which payroll  deductions will be made and held for the purchase
of Common Stock at the end of the Plan Period.

   4. Participation.  An employee eligible on the Offering  Commencement Date of
any Offering may  participate  in such Offering by completing  and  forwarding a
payroll  deduction   authorization   form  prior  to  the  applicable   Offering
Commencement Date to the employee's  appropriate  human resources  department no
later than the date  specified  on the form.  The form will  authorize a regular
payroll deduction from the Compensation received by the employee during the Plan
Period.  Unless an employee  files a new form or withdraws from the Plan, his or
her deductions and purchases will continue at the same rate for future Offerings
under the Plan as long as the Plan  remains in effect.  The term  "Compensation"
means the  amount of money  reportable  on the  employee's  Federal  Income  Tax
Withholding Statement,  including overtime,  bonuses and sales commissions,  but
excluding  allowances and  reimbursements  for expenses,  income or gains on the
exercise of Company stock options and similar items, whether or not shown on the
employee's Federal Income Tax Withholding Statement.

   5. Deductions.  The Company will maintain payroll deduction  accounts for all
participating  employees.  With respect to any Offering made under this Plan, an
employee may authorize a payroll  deduction equal to any whole number percentage
between 1% and 10% of the Compensation he or she receives during the Plan Period
or such shorter period during which deductions from payroll are made. Any change
in Compensation during the Plan Period will result in an automatic corresponding
change in the dollar amount withheld.

No employee may be granted an Option (as defined in Section 9) which permits his
or her rights to purchase  Common  Stock under this Plan and any other  employee
stock  purchase  plan (as defined in Section  423(b) of the Code) of the Company
and its  subsidiaries,  to accrue at a rate  which  exceeds  $25,000 of the fair
market value of such Common Stock (determined at the Offering  Commencement Date
of the Plan Period) for each calendar year in which the Option is outstanding at
any time.

   6.  Deduction  Changes.  An employee may decrease or  discontinue  his or her
payroll  deduction once during any Plan Period by filing a new payroll deduction
authorization  form.  However,  an employee  may not increase his or her payroll
deduction during a Plan Period.  If an employee elects to discontinue his or her
payroll  deductions during a Plan Period,  but does not elect to withdraw his or
her funds  pursuant  to  Section 8 hereof,  funds  deducted  prior to his or her
election to  discontinue  will be applied to the purchase of Common Stock on the
Exercise Date (as defined below).

   7. Interest. Interest will not be paid on any employee accounts.


   8.  Withdrawal  of Funds.  An employee  may at any time prior to the close of
business  on  the  last  business  day in a  Plan  Period  and  for  any  reason
permanently  draw out the  balance  accumulated  in the  employee's  account and
thereby withdraw from participation in an Offering.  Partial withdrawals are not
permitted. The employee may not begin participation again during


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the remainder of the Plan Period. The employee may participate in any subsequent
Offering in accordance with terms and conditions established by the Board or the
Committee.

   9. Purchase of Shares. On the Offering Commencement Date of each Plan Period,
the Company will grant to each eligible  employee who is then a  participant  in
the Plan an option  ("Option") to purchase on the last business day of such Plan
Period (the "Exercise Date"), at the Option Price hereinafter provided for, such
number of whole shares of Common Stock of the Company  reserved for the purposes
of the Plan as does not exceed the number of shares which can be purchased under
the limit on accruals in any calendar year set forth in Section 5.

The purchase price for each share  purchased will be 85% of the closing price of
the Common  Stock on (i) the first  business day of such Plan Period or (ii) the
Exercise Date,  whichever  closing price shall be less. Such closing price shall
be (a) the closing price on any national securities exchange on which the Common
Stock is  listed,  (b) the  closing  price  of the  Common  Stock on the  Nasdaq
National  Market or (c) the average of the  closing bid and asked  prices in the
over-the-counter-market,  whichever  is  applicable,  as  published  in The Wall
Street  Journal.  If no sales of Common Stock were made on such a day, the price
of the  Common  Stock for  purposes  of clauses  (a) and (b) above  shall be the
reported price for the next preceding day on which sales were made.

Each employee who continues to be a participant in the Plan on the Exercise Date
shall be deemed to have  exercised his or her Option at the Option Price on such
date and shall be deemed to have  purchased  from the Company the number of full
shares of Common  Stock  reserved  for the  purpose  of the Plan that his or her
accumulated payroll deductions on such date will pay for pursuant to the formula
set forth  above  (but not in excess of the  maximum  number  determined  in the
manner set forth above).

Any balance remaining in an employee's payroll deduction account at the end of a
Plan Period will be  automatically  refunded  to the  employee,  except that any
balance which is less than the purchase  price of one share of Common Stock will
be  carried  forward  into the  employee's  payroll  deduction  account  for the
following  Offering,  unless  the  employee  elects  not to  participate  in the
following  Offering  under the Plan, in which case the balance in the employee's
account shall be refunded.

   10.  Issuance of  Certificates.  Certificates  representing  shares of Common
Stock  purchased  under the Plan may be issued only in the name of the employee,
in the name of the  employee  and another  person of legal age as joint  tenants
with rights of survivorship, or (in the Company's sole discretion) in the street
name of a  brokerage  firm,  bank or  other  nominee  holder  designated  by the
employee.  The  Company  may,  in its sole  discretion  and in  compliance  with
applicable laws,  authorize the use of book entry registration of shares in lieu
of issuing stock certificates.

   11. Rights on Retirement, Death or Termination of Employment. In the event of
a participating  employee's termination of employment prior to the last business
day of a Plan Period,  no payroll  deduction shall be taken from any pay due and
owing to an employee and the balance in the employee's  account shall be paid to
the  employee or, in the event of the  employee's  death,  (a) to a  beneficiary
previously designated in a revocable notice signed by the


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employee  (with any  spousal  consent  required  under  state law) or (b) in the
absence of such a designated  beneficiary,  to the executor or  administrator of
the  employee's  estate or (c) if no such  executor  or  administrator  has been
appointed  to the  knowledge  of the  Company,  to such other  person(s)  as the
Company may, in its discretion, designate. If, prior to the last business day of
the Plan Period, the Eligible  Subsidiary by which an employee is employed shall
cease to be a subsidiary of the Company,  or if the employee is transferred to a
subsidiary of the Company that is not an Eligible Subsidiary, the employee shall
be deemed to have terminated employment for the purposes of this Plan.

   12.  Optionees  Not  Stockholders.  Neither  the  granting of an Option to an
employee nor the deductions from his or her pay shall constitute such employee a
stockholder  of the shares of Common Stock  covered by an Option under this Plan
until such shares have been purchased by and issued to him or her.

   13. Rights Not Transferable. Rights under this Plan are not transferable by a
participating   employee  other  than  by  will  or  the  laws  of  descent  and
distribution,  and are  exercisable  during the employee's  lifetime only by the
employee.

   14.  Application  of Funds.  All funds  received or held by the Company under
this Plan may be  combined  with other  corporate  funds and may be used for any
corporate purpose.

   15.  Adjustment in Case of Changes  Affecting Common Stock. In the event of a
subdivision of outstanding  shares of Common Stock, or the payment of a dividend
in Common  Stock,  the number of shares  approved  for this Plan,  and the share
limitation set forth in Section 9, shall be increased proportionately,  and such
other  adjustment  shall be made as may be deemed  equitable by the Board or the
Committee.  In the event of any other change  affecting the Common  Stock,  such
adjustment  shall  be  made  as may be  deemed  equitable  by the  Board  or the
Committee to give proper effect to such event.

   16.  Merger.  If the  Company  shall at any time  merge or  consolidate  with
another  corporation  and  the  holders  of the  capital  stock  of the  Company
immediately prior to such merger or consolidation  continue to hold at least 80%
by voting power of the capital stock of the surviving  corporation  ("Continuity
of  Control"),  the holder of each Option then  outstanding  will  thereafter be
entitled to receive at the next  Exercise  Date upon the exercise of such Option
for each share as to which such Option  shall be  exercised  the  securities  or
property  which a holder of one share of the Common  Stock was  entitled to upon
and at the time of such merger or consolidation,  and the Board or the Committee
shall take such steps in  connection  with such merger or  consolidation  as the
Board or the  Committee  shall deem  necessary to assure that the  provisions of
Paragraph 15 shall thereafter be applicable,  as nearly as reasonably may be, in
relation  to the said  securities  or  property  as to which such holder of such
Option might thereafter be entitled to receive thereunder.

In the event of a merger or  consolidation  of the Company  with or into another
corporation which does not involve Continuity of Control, or of a sale of all or
substantially all of the assets of the Company while unexercised  Options remain
outstanding  under the Plan,  (a) subject to the  provisions  of clauses (b) and
(c), after the effective date of such transaction, each holder of an outstanding
Option shall be entitled,  upon  exercise of such Option,  to receive in lieu of
shares of


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Common Stock,  shares of such stock or other securities as the holders of shares
of Common Stock received pursuant to the terms of such  transaction;  or (b) all
outstanding  Options may be cancelled by the Board or the Committee as of a date
prior to the effective date of any such  transaction and all payroll  deductions
shall be paid out to the participating employees; or (c) all outstanding Options
may be cancelled by the Board or the Committee as of the  effective  date of any
such transaction,  provided that notice of such  cancellation  shall be given to
each holder of an Option,  and each holder of an Option  shall have the right to
exercise such Option in full based on payroll deductions then credited to his or
her account as of a date  determined by the Board or the  Committee,  which date
shall  not be less  than ten (10)  days  preceding  the  effective  date of such
transaction.

   17.  Amendment of the Plan. The Board may at any time, and from time to time,
amend this Plan in any  respect,  except  that (a) if the  approval  of any such
amendment by the  stockholders  of the Company is required by Section 423 of the
Code, such amendment shall not be effected without such approval,  and (b) in no
event may any  amendment  be made which  would  cause the Plan to fail to comply
with Section 423 of the Code.

   18.  Insufficient  Shares.  In the event  that the total  number of shares of
Common Stock  specified in elections to be purchased under any Offering plus the
number of shares purchased under previous  Offerings under this Plan exceeds the
maximum  number of shares  issuable  under this Plan, the Board or the Committee
will allot the shares then available on a pro rata basis.

   19.  Termination of the Plan.  This Plan may be terminated at any time by the
Board.   Upon   termination  of  this  Plan  all  amounts  in  the  accounts  of
participating employees shall be promptly refunded.

   20. Governmental  Regulations.  The Company's  obligation to sell and deliver
Common Stock under this Plan is subject to listing on a national  stock exchange
or quotation on the Nasdaq National Market and the approval of all  governmental
authorities  required in connection with the authorization,  issuance or sale of
such stock.

The Plan shall be governed by  Massachusetts  law except to the extent that such
law is preempted by federal law.

   21. Issuance of Shares.  Shares may be issued upon exercise of an Option from
authorized  but unissued  Common Stock,  from shares held in the treasury of the
Company, or from any other proper source.

   22.  Notification upon Sale of Shares.  Each employee agrees, by entering the
Plan, to promptly give the Company notice of any disposition of shares purchased
under the Plan where such disposition  occurs within two years after the date of
grant of the Option pursuant to which such shares were purchased.

   23. Effective Date and Approval of  Stockholders.  The Plan shall take effect
on either (i) a date promptly after the Special  Meeting  approving such Plan if
such  commencement  date is on or  before  March  31,  1999 or (ii) July 1, 1999
subject to  approval by the  stockholders  of the Company as required by Section
423 of the Code,  which approval must occur within twelve months of the adoption
of the Plan by the Board.


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                                        Adopted by the Board of Directors
                                        on September 1, 1998


                                        Approved by the Stockholders on
                                        January 26, 1999