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                                                                     EXHIBIT 4.9

                         UNIT PURCHASE OPTION AGREEMENT



THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS AND NEITHER THE SECURITIES
NOR ANY INTEREST THEREIN MAY BE OFFERED, SOLD, TRANSFERRED, PLEDGED OR OTHERWISE
DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH
ACT OR SUCH LAWS OR AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT OR SUCH LAWS,
WHICH, IN THE OPINION OF COUNSEL FOR THE HOLDER, WHICH COUNSEL AND OPINION ARE
REASONABLY SATISFACTORY TO COUNSEL FOR THIS CORPORATION, IS AVAILABLE.



                              Dated: March 30, 1994

                         Option to Purchase 15,675 Units

                       VOID AFTER 5:00 P.M. (EASTERN TIME)

                                       ON
                                  May 31, 1999

                          AMERICAN PSYCH SYSTEMS, INC.



                   Option to Purchase 15,675 Units, each Unit
                    consisting of one share of Common Stock,
                    par value $.001 per share, and a warrant
                 to purchase one-quarter share of Common Stock,
                            par value $.001 per share


      AMERICAN PSYCH SYSTEMS, INC., a Delaware corporation (the "Company"),
hereby certifies that ________________ (the "Holder"), his successors and
assigns, for value received, is entitled to purchase from the Company at any
time after the date hereof, and before 5:00 P.M. (Eastern Time) on May 31, 1999
(the "Exercise Period"), ______ Units (the "UPO Units") of the Company at a
purchase price per Unit equal to $1.00 per UPO Unit (hereinafter, the "Unit
Purchase Price", and as adjusted as provided herein, the "Exercise Price').
This Unit

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Purchase Option Agreement (the "UPO Agreement") represents the Unit Purchase
Option (the "UPO") pursuant to a certain Sales Agency Agreement dated as of
February 15, 1994, between the Company and KBL Healthcare, Inc. Each UPO Unit
consists of one share (the "UPO Shares") of Common Stock, par value $.001 per
share ("Common Stock"), of the Company, and one warrant expiring May 31, 1999
(the "UPO Warrants") to purchase one-quarter share of Common Stock of the
Company (the "UPO Warrant Shares"). Except for the Exercise Period, the UPO
Warrants shall be identical to the warrants included in the Units sold by the
Company pursuant to the Sales Agency Agreement (the "Unit Warrants").

      1. EXERCISE OF UPOS. Upon presentation and surrender of this UPO
Agreement, with the attached Purchase Form duly executed, at the principal
office of the Company at One Democracy Plaza, 6701 Democracy Boulevard, Suite
410, Bethesda, Maryland 20817, together with a certified or bank cashier's check
payable to the Company in the amount of the Exercise Price multiplied by the
number of Units of the Company being purchased, the Company shall deliver to the
holder hereof, as promptly as practicable, certificates representing the UPO
Shares and UPO Warrants underlying the UPO Units being purchased. This UPO may
be exercised in whole or in part; and, in case of exercise hereof in part only,
the Company, upon surrender hereof, will deliver to the Holder a new UPO
Agreement entitling said holder to purchase the number of UPO Units as to which
this UPO Agreement has not been exercised.

      2. RIGHTS AND OBLIGATIONS OF UPO HOLDERS. The holder of this UPO Agreement
shall not, by virtue hereof, be entitled to any rights of a stockholder in the
Company, either at law or in equity; PROVIDED, HOWEVER, in the event that any
certificate representing shares of the Company's Common Stock is issued to the
holder hereof upon exercise of some or all of the UPOs represented hereby, such
holder shall, for all purposes, be deemed to have become the holder of


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record of such stock on the date on which this UPO Agreement, together with a
duly executed Purchase Form, was surrendered and payment of the purchase price
was made, irrespective of the date of delivery of such share certificate. The
rights of the holder of this UPO Agreement are limited to those expressed herein
and the holder of this UPO Agreement, by his acceptance hereof, consents to and
agrees to be bound by and to comply with all the provisions of this UPO
Agreement, including, without limitation, all the obligations imposed upon the
holder hereof by Section 5. In addition, the Holder of this UPO Agreement, by
accepting the same, agrees that the Company may deem and treat the person in
whose name this UPO Agreement is registered as the absolute, true and lawful
owner for all purposes whatsoever, and the Company shall not be affected by any
notice to the contrary.

      3.    UPO SHARES AND UPO WARRANTS.

            3.1 UPO SHARES. The Company covenants and agrees that all UPO Shares
delivered as part of the UPO Units upon exercise (in accordance with the terms
and conditions set forth herein) of this UPO Agreement will, upon delivery, be
duly and validly authorized and issued, fully paid and nonassessable, and free
from all stamp taxes, liens, and charges with respect to the purchase thereof.

            3.2 UPO WARRANTS. The Company covenants and agrees that all UPO
Warrants delivered upon exercise of this UPO Agreement will, upon delivery, be
duly and validly authorized and issued, valid and binding obligations of the
Company, enforceable in accordance with their terms, and free from all stamp
taxes, liens, and charges with respect to the purchase thereof. In addition, the
Company agrees at all times to reserve and keep available an



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authorized number of shares of Common Stock sufficient to permit the exercise in
full of the UPOs and the UPO Warrants.

      4.    RESTRICTIONS ON TRANSFERABILITY; COMPLIANCE WITH SECURITIES ACT.

            This UPO, the UPO Shares, the UPO Warrants and the UPO Warrant
Shares shall not be transferable except in compliance with the provisions of the
Securities Act of 1933, as amended (the "Securities Act"), and state Blue Sky
laws. The Holder is purchasing the Units for the Holder's own account, for
investment and not with a view to resale or distribution except In compliance
with the Securities Act. The Holder acknowledges that each certificate
representing the UPO Shares and the UPO Warrants shall be stamped or otherwise
imprinted with a legend substantially in the form of the legend on the first
page hereof.

      5. REGISTRATION RIGHTS. The UPO Shares and the UPO Warrant Shares are
entitled to certain registration rights pursuant to that certain Registration
Rights Agreement made on behalf of KBL and its designees by the Company.

      6.    ADJUSTMENTS.

            6.1 Any event which would have the effect of causing an adjustment
to be made to the exercise price, of, or the number of shares of Common Stock or
the nature of securities issuable upon exercise of, the Unit Warrants, shall
have the same effect on the Exercise Price, the number of UPO Shares and the
nature of securities issuable upon exercise of, the UPOs represented hereby. In
addition, except for the Exercise Period, the UPO Warrants shall be identical to
the Unit Warrant, and any and all changes made to the exercise price, number of
shares of Common stock or the nature of securities issuable upon exercise of,
the Unit



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Warrants shall be simultaneously made to the UPO Warrants as if the UPO Warrants
were outstanding on the date of such adjustment.

            6.2 NOTICE TO QPO HOLDERS OF ADJUSTMENT. Whenever an adjustment is
made, as herein provided, the Company shall give each Holder of UPOs a notice
(i) setting forth and describing the adjustment which has been made, the
adjusted Exercise Price and the exercise price of the UPO Warrants and the
adjusted number of shares issuable upon exercise of the UPO Units and the UPO
Warrants, and (ii) showing in reasonable detail the computations and the facts
upon which such adjustments are based.

            6.3 NOTICE TO UPO HOLDERS OF STOCK DIVIDENDS, REORGANIZATIONS, ETC.
If at any time after the date hereof any event set forth in Paragraph 3.3 of the
Unit Warrants occurs, then, in any one or more of said cases, the Company shall
cause to be mailed to the Holders of UPOs, pursuant to the provisions and time
periods set forth in Paragraph 3.3 of the Unit Warrants, written notice of the
date upon which the books of the Company shall close or a record shall be taken
for purposes of such dividend, distribution or subscription rights or upon which
such reorganization, reclassification, consolidation, merger, sale, dissolution,
liquidation or winding-up shall take place, as the case may be. Such notice
shall also set forth facts as shall indicate the effect of such action (to the
extent such effect may be known at the date of such notice) on the Exercise
Price and the kind and amount of the shares of stock and other securities and
property deliverable upon exercise of the UPOs. Such notice shall also specify
the date, pursuant to Paragraph 3.3 of the Unit Warrants, as of which the
Holders of record of Common Stock shall participate in said dividend,
distribution or subscription rights or shall be entitled to exchange their
shares of Common Stock for securities or other property deliverable upon such
reorganization, reclassification, consolidation, merger, sale, dissolution,
liquidation or winding-



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up, as the case may be (on which date in the event of voluntary or involuntary
dissolution, liquidation or winding-up of the Company, the right to exercise the
UPOs shall terminate).

            6.4 FRACTIONAL SHARES. The Company shall not be required to issue
any fraction of a share of Common Stock upon the exercise of the UPOs or a share
of Common Stock upon the exercise of the UPO Warrants. If more than one such UPO
or UPO Warrant shall be surrendered for exercise at one time by the same Holder,
the number of full shares of Common Stock, as the case may be, which shall be
issuable upon exercise thereof shall be computed on the basis of the aggregate
number of UPOs or UPO Warrants so exercised. If any fractional interest in a
share of Common Stock, as the case may be, shall be deliverable upon the
exercise of any UPO or UPO Warrant, the Company shall make an adjustment
therefor in cash equal to the fair market value of any such fractional interest
as it shall appear on the public market, or if there is no public market for
such shares, then as shall be reasonably determined by the Company.

      7. SURVIVAL. The various rights and obligations of the Holder hereof and
of the Company as set forth in Sections 4, 5 and 6 hereof shall survive the
exercise of the UPOs represented hereby end the surrender of this UPO Agreement,
and upon the surrender of this UPO Agreement and the exercise of all of the UPOs
represented hereby, the Holder and the Company shall, if requested, deliver to
the other its written acknowledgement of its continuing obligations under said
Sections.

      8. NOTICE. All notices required or permitted by this UPO Agreement to be
given or made by the Company shall be given or made by first class mail, postage
prepaid, addressed to the registered Holder hereof or the record owner of UPO
Units represented hereby at the address



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of such Holder or owner, as the case may be, as shown on the books of the
Company. Notices required or permitted to be given to the Company shall be sent
to:

                        American Psych Systems, Inc.
                        One Democracy Plaza,
                        6701 Democracy Boulevard
                        Suite 410
                        Bethesda, Maryland  20817
                        Attention: Kenneth Kessler, M.D. President

and a copy thereof to:

                        Michael J. Wishner, Esq.
                        Michaels & Wishner, P.C.
                        1140 Connecticut Avenue, N.W.
                        Suite 900
                        Washington, D.C.  20036

      9. MUTILATED OR MISSING UPO AGREEMENT. In case this UPO Agreement shall be
mutilated, lost, stolen or destroyed, the Company may, in its discretion, issue
and deliver in exchange and substitution for and upon cancellation of the
mutilated UPO Agreement or in lieu of and substitution of the UPO Agreement
lost, stolen or destroyed, a new UPO Agreement of like tenor and representing an
equivalent right or interest, but only upon receipt of evidence satisfactory to
the Company of such loss, theft, or destruction of such UPO Agreement and, in
the case of a lost, stolen or destroyed UPO Agreement, indemnity, if requested,
also satisfactory to the Company. Applicants for such substitute UPO Agreements
shall also comply with such other reasonable regulations and pay such reasonable
charges as the Company may prescribe.


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      10. GOVERNING LAW. This UPO Agreement shall be deemed made under the laws
of the State of New York and for all purposes shall be construed in accordance
with the laws of said State, except for provisions regarding conflicts of law.

                                          AMERICAN PSYCH SYSTEMS, INC.



                                          By:
                                             ---------------------------------
                                                Kenneth Kessler, M.D.
                                                President


ATTEST:



By:
   ---------------------------
      John C. Heffner
      Secretary


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                                  PURCHASE FORM
                                                                       , 19
                                                           ------------    --

TO:   AMERICAN PSYCH SYSTEMS, INC.

      The undersigned hereby irrevocably elects to exercise the attached UPO to
the extent of _________ UPO Units of American Psych Systems, Inc., and hereby
makes payment of $_______ in payment of the aggregate price thereof.

      If the exercise of the UPO is not covered by a registration statement
effective under the Securities Act, the undersigned represents that

      (i) the undersigned is acquiring such UPO Units for investment for the
undersigned's own account, not as nominee or agent, and not with a view to the
sale or distribution of any part thereof and the undersigned has no present
intention of and has not signed or otherwise arranged for the selling, granting
any participation in, or otherwise distributing the same,

      (ii) the undersigned has such knowledge and experience in financial and
business matters as to be capable of evaluating the merits and risks of the
undersigned's investment in the UPO Units,

      (iii) the undersigned has received all of the information the undersigned
has requested from the Company and considers necessary or appropriate for
deciding whether to purchase the UPO Units,

      (iv) the undersigned has the ability to bear the economic risks of the
undersigned's prospective investment,

      (v) the undersigned is able, without materially impairing the
undersigned's financial condition, to hold the UPO Units for an indefinite
period of time and to suffer complete loss on the undersigned's investment,

      (vi) the undersigned understands and agrees that (A) the undersigned may
be unable to readily liquidate the undersigned's investment in the UPO Units and
that the UPO Units must be held indefinitely unless a subsequent disposition
thereof is registered or qualified under the Securities Act and applicable state
securities or Blue Sky laws or is exempt from such registration or
qualification, and that the Company is not required to register the same or to
take any action or make such an exemption available except to the extent
provided in the registration rights set forth in Section 5 of the attached UPO;
and (B) the exemption from registration under the Securities Act afforded by
Rule 144 promulgated by the Securities and Exchange Commission ("Rule 144")
depends upon the satisfaction of various conditions by the undersigned and the
Company and that, if applicable, Rule 144 affords the basis for sales under
certain circumstances in limited amounts, and that if such exemption is utilized
by the undersigned, such conditions must be fully complied with by the
undersigned and the Company, as required by Rule 144,


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      (vii) the undersigned either (A) is familiar with the definition of and
the undersigned is an "accredited investor" within the meaning of such term
under Rule 501 of Regulation D promulgated under the Securities Act, or (B) is
providing a written opinion, addressed to the Company, of counsel to the
undersigned which counsel and opinion shall be reasonably satisfactory to the
Company, to the effect that the sale of the UPO Units may be made without
registration under the Securities Act or any applicable state securities and
Blue Sky laws, and

      (viii) the address set forth below is the true and correct address of the
undersigned's residence.

            INSTRUCTIONS FOR REGISTRATION AND DELIVERY OF SECURITIES



NAME:
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                  (Please typewrite or print in block letters)





ADDRESS (INCLUDING ZIP CODE):
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                (Social Security or other tax identifying number)



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


                                          By:
                                             ---------------------------------



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                                 ASSIGNMENT FORM

      FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto the Assignee named below all of the rights of the undersigned represented
by the attached UPO Agreement, with respect to the number of UPO Units set forth
below.

<TABLE>

                                                                Federal I.D. No.
  NAME OF ASSIGNEE         ADDRESS        NO. OF UPO UNITS   OR SOCIAL SECURITY NO.
  ----------------         -------        ----------------   ---------------------
<S>                      <C>            <C>                 <C>
</TABLE>







and does hereby irrevocably constitute and appoint              attorney to make
                                                   ------------
such transfer on the books of American Psych Systems, Inc. maintained for that
purpose, with full power of substitution in the premises.

Dated:                        , 19
      ------------------------    --




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                                          By:
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