Exhibit 10.27


                                 March 23, 2000



Resurgence Asset Management, L.L.C.
10 New King Street, 1st Floor
White Plains, NY 10604

         Re:  Exchange of Senior Discount Notes

Ladies/Gentlemen:

   The purpose of this letter is to confirm the agreement of Arch Communications
Group, Inc. ("Arch") and Resurgence Asset Management,  L.L.C.  ("Resurgence") as
follows:

   1. Exchange of Senior Discount Notes.  Resurgence  agrees to exchange,  or to
cause the exchange of, $100,000,000 in principal amount at maturity of Arch's 10
7/8% Senior  Discount  Notes Due 2008 (the "Notes")  owned by Resurgence  and/or
related entities (collectively,  the "Resurgence Entities") for 1,000,000 shares
of Arch's Series D Convertible  Preferred  Stock ("Series D Stock") as described
in Section 2 below.

   2. Terms of Preferred Stock.

   (a) The Series D Stock will:

      o  be convertible  into Arch's Common Stock at the holders'  option at any
         time at an exchange  ratio of 66.1318 shares of Common Stock per $1,000
         principal amount at maturity;

      o  be subject to mandatory conversion into Common Stock upon completion of
         Arch's pending merger with Paging Network, Inc. ("PageNet");

      o  commencing March 15, 2001, bear semi-annual dividends at the rate of 10
         7/8% per  annum,  payable  at  Arch's  option  in cash or  through  the
         issuance of Arch's Series E Preferred Stock ("Series E Stock");

      o  be subject to mandatory  redemption  on March 15, 2008 if redemption is
         then permitted by applicable law;

      o  vote with the Common Stock on an as-converted basis; and

      o  rank upon  liquidation  senior to the common stock and on a parity with
         Arch's Series C Convertible Preferred Stock.

   (b) If Arch issues  Series E Stock as a dividend  on the Series D Stock,  the
Series E Stock will be identical to the Series D Stock except that it will not:

      o  be subject to conversion into common stock;



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      o  have any voting rights except as required by law; or

      o  bear dividends.

   (c) The terms of the Series D Stock and Series E Stock  shall  conform to the
descriptions  contained  above  and  shall  be  contained  in a  Certificate  of
Designations  filed with the Secretary of State of Delaware.  The Certificate of
Designations  shall  be in  such  form as is  mutually  agreed  to by  Arch  and
Resurgence.

   3.  Representations.  Arch  and  Resurgence  (on  behalf  of  itself  and the
Resurgence Entities) hereby represent, warrant and agree as follows:

   (a) Resurgence approached Arch and initiated negotiations with Arch regarding
the exchange of Notes for Series D Stock as  contemplated  hereby.  Neither Arch
nor  anyone  acting  on  Arch's  behalf  approached  Resurgence  regarding  this
transaction.

   (b) Resurgence acknowledges that the transaction contemplated hereby is
intended  to be exempt  from  registration  by virtue of Section  3(a)(9) of the
Securities Act of 1933, as amended (the "Securities  Act").  Resurgence knows of
no reason why such exemption is not available.

   (c) Resurgence has had such  opportunity as it has deemed  adequate to obtain
from  representatives  of  Arch  such  information  as is  necessary  to  permit
Resurgence  to  evaluate  the merits and risks of the  transaction  contemplated
hereby.

   (d)  Resurgence  has  sufficient   experience  in  business,   financial  and
investment  matters to be able to evaluate the risks involved in the acquisition
of the Series D Stock, the Series E Stock and the Common Stock issued in respect
thereto  and to  make an  informed  investment  decision  with  respect  to such
acquisition.

   (e) The shares of Series D Stock, Series E Stock and Common Stock issued upon
conversion  of the  Series D Stock and  Series E Stock  will not be  "restricted
securities"  within  the  meaning  of Rule 144 under  the  Securities  Act.  The
certificate(s)  representing the Shares will not bear a restrictive legend under
the Securities Act.

   4.  Conditions  to Closing.  The  exchange of the Notes for Series D Stock as
contemplated hereby is subject to satisfaction of the following conditions:

   (a)  Resurgence  Entities  shall  have  sold to a  third  party  selected  by
Resurgence (the "Third Party") $53,865,000 principal amount at maturity of Notes
owned by Resurgence Entities (the "Third Party Notes") and the Third Party shall
have  exchanged  all of the Third Party Notes for shares of Arch Common Stock at
an exchange ratio of 66.1318 shares of Common Stock per $1,000  principal amount
at maturity.


   (b) Arch's  stockholders  shall have  approved the  proposed  increase in the
number of authorized  shares of Common Stock from  65,000,000 to 150,000,000 and
an amendment to


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Arch's  Certificate of  Incorporation  reflecting  such increase shall have been
filed with the Secretary of State of Delaware.

   (c) A  Certificate  of  Designations  establishing  the terms of the Series D
Stock and Series E Stock and  consistent  with the terms  hereof shall have been
filed with the Secretary of State of Delaware.

   (d) Arch shall have  reserved for issuance  such number of shares of Series D
Stock,  Series E Stock and Common Stock as may be issuable  from time to time in
connection with the transactions contemplated hereby.

   (e) Arch  and the  Resurgence  Entities  shall  have  received  all  required
regulatory approvals in connection with the transactions contemplated hereby.

   (f) The transactions  contemplated  hereby shall have been approved by Arch's
bank lenders.

   (g) The  exchange  of all Notes for  Series D Stock and the  exchange  of all
Third  Party  Notes for  Common  Stock as  contemplated  hereby  shall have been
completed by April 30, 2000.

   5. Entire Agreement.  This Agreement  represents the entire understanding and
agreement  between the parties  hereto with respect to the subject matter hereof
and  supersedes  all  prior  oral  and  written  and  all  contemporaneous  oral
negotiations,  commitments and understandings  between such parties. The parties
may amend or modify this  Agreement,  in such manner as may be agreed upon, only
by a written instrument executed by the parties hereto.

   6.  Expenses.  Each party shall pay its own expenses in connection  with this
Agreement and the transactions contemplated hereby.

   7.  Governing  Law.  This  Agreement  shall be governed by and  construed  in
accordance with the laws of the State of Delaware.

   8. Severability.  The invalidity or unenforceability of any provision of this
Agreement shall not affect the validity or enforceability of any other provision
of this Agreement.

   9. Counterparts.  This Agreement may be executed in two or more counterparts,
each of which shall be deemed to be an  original,  but all of which shall be one
and the same document.

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   Please confirm your agreement by signing in the space indicated below.

                                        ARCH COMMUNICATIONS GROUP, INC.


                                        By:     /s/ J. Roy Pottle
                                               ------------------------


                                        Title: Chief Financial Officer
                                               ------------------------


  Agreed:

  RESURGENCE ASSET MANAGEMENT, L.L.C.


  By:    /s/ Robert T. Symington
         ----------------------------


  Title: Managing Director
         ----------------------------















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