EXHIBIT 99.1


                                                                   April 5, 2000


Dear Participant:

     As of March 29, 2000, the trust ("DRP Trust")  established for the Columbia
Federal  Savings  Bank  (now  known as CFS Bank,  the  "Bank")  Recognition  and
Retention Plan for Outside  Directors ("DRP") held 13,982 shares of common stock
of Haven Bancorp, Inc. (the "Company"), the parent holding company for the Bank.
As a  participant  in the DRP,  you may  direct  the voting of the shares of the
Company's common stock held by the DRP Trust that have been granted to you under
the DRP.

     Chase Manhattan Bank has been appointed as an unrelated  corporate  trustee
for the DRP  Trust  (the  "DRP  Trustee").  We,  the  Board  of  Directors,  are
forwarding to you the attached Vote Authorization Form, provided for the purpose
of conveying your voting  instructions to the DRP Trustee.  The DRP Trustee will
vote those shares of the Company's  common stock held in the DRP Trust that have
been granted to participants in accordance with  instructions  received from the
participants.  If the DRP Trustee  does not  receive  voting  instructions  with
respect to shares that have been granted to  participants,  the DRP Trustee will
vote such shares in the same  proportion as it votes the shares for which it has
received voting instructions.

     At this time to direct the  voting of shares  granted to you under the DRP,
you must complete and sign the enclosed Vote Authorization Form and return it in
the  accompanying  envelope to Ellen  Philip  Associates,  Inc.  ("Ellen  Philip
Associates").  Your vote will not be revealed,  directly or  indirectly,  to any
director, officer or other employee of the Company or the Bank. Your shares will
be tallied by Ellen Philip  Associates  on a  confidential  basis.  Ellen Philip
Associates will then provide the tabulated  results to the DRP Trustee.  The DRP
Trustee  will  then  vote  the  shares  in the DRP  Trust  based  on the  voting
instructions it has received from participants, as described above.



                                                      Sincerely,



                                                      The Board of Directors







                               HAVEN BANCORP, INC.

                         ANNUAL MEETING OF STOCKHOLDERS
                                  May 17, 2000

                             VOTE AUTHORIZATION FORM


     I, having signed this form,  hereby  instruct the Columbia  Federal Savings
Bank  Recognition  and Retention Plan for Outside  Directors  ("DRP") Trustee to
vote all shares of common stock of Haven Bancorp,  Inc.  granted to me under the
DRP as set forth below at the Annual Meeting of  Stockholders  to be held on May
17, 2000, and at any adjournment or postponement thereof.

                                                 Please mark your
                                                 votes as indicated    [X]
                                                 in this example

                 THE BOARD OF DIRECTORS RECOMMENDS A VOTE "FOR"
                          EACH OF THE LISTED PROPOSALS.

1.   The Election as directors of all nominees listed:  (Except as marked to the
     contrary  below) Philip S.  Messina,  Msgr.  Thomas J. Hartman,  Michael A.
     McManus, Jr.

         FOR                                                  VOTE WITHHELD
         [_]                                                        [_]

INSTRUCTION:  To  withhold  your vote for any  individual  nominee,  write  that
nominee's name on the space provided below:

- ---------------------------------------

2.   The ratification of the appointment of KPMG LLP as independent  auditors of
     Haven Bancorp, Inc. for the fiscal year ending December 31, 2000.

         FOR                      AGAINST                           ABSTAIN
         [_]                          [_]                             [_]

3.   Approval of the  proposal to adjourn or postpone  the Annual  Meeting  once
     called to order to another time and/or place for the purpose of  soliciting
     additional proxies, if necessary.

         FOR                     AGAINST                           ABSTAIN
         [_]                         [_]                             [_]

I  acknowledge  that I have  received from the Company prior to the execution of
this vote  authorization  form, a Notice of Annual  Meeting of  Stockholders,  a
Proxy  Statement  dated April 5, 2000, the Annual Report to  Stockholders  and a
letter dated April 5, 2000 from the Board of Directors.

I understand that my voting instructions are solicited by the Board of Directors
on behalf of the DRP Trustee for the Annual  Stockholders  Meeting to be held on
May 17, 2000, and at any adjournment or postponement thereof. The DRP Trustee is
hereby  authorized to vote the shares granted to me, in its trust  capacity,  as
indicated above.


                                                 -------------------------------
                                                 Signature


- -------------------------------
Date

Please sign, date and return this form in the enclosed business reply envelope.