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                                                                 EXHIBIT 4.11

                         SHAREHOLDER'S RIGHTS AGREEMENT

      THIS SHAREHOLDER'S RIGHTS AGREEMENT (the "AGREEMENT") is dated October 18,
1999, by and between American Psych Systems Holdings, Inc., a Delaware
corporation ("APSH"), and Combined Benefits Management, Inc., a Montana
corporation ("CBMI") (APSH and CBMI are sometimes hereinafter referred to
collectively as the "PARTIES" and each individually as a "PARTY").

                                    RECITALS

      A.    CBMI and APSH are parties to a Stock Purchase Agreement dated
October 8, 1999 (the "Stock Purchase Agreement"), pursuant to which APSH is
purchasing from CBMI 100% of the issued and outstanding shares of Vydas
Resources, Inc. (the "VRI Shares"), contemporaneously with the execution and
delivery of this Agreement.

      B.    As part of the  consideration  for the purchase and sale,  APSH is
delivering to CBMI the Buyer's Shares, as defined below.

      C.    It is an express condition to each Party's obligation to consummate
the transactions contemplated by the Stock Purchase Agreement that the Parties
enter into this Agreement to delineate certain rights, privileges, restrictions,
and limitations with respect to the Buyer's Shares and related matters.


NOW, THEREFORE, in consideration of the premises, and the mutual promises set
forth in this Agreement and in the Stock Purchase Agreement and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Parties agree as follows:

1. DEFINITIONS

      As used in this Agreement, the following terms shall have the following
respective meanings:

      "AFFILIATE" means any entity that directly or indirectly, through one or
more intermediaries, controls, or is controlled by, or is under common control
with, another entity.

      "BEST EFFORTS" shall mean the efforts that a prudent business person
desirous of achieving a result would use under similar circumstances to ensure
that such result is achieved as expeditiously as reasonably possible.

      "BUYER'S SHARES" means those shares of APSH stock delivered to CBMI
pursuant to the Stock Purchase Agreement between the Parties.

      "CHANGE OF CONTROL" means a transfer or exchange in the power or authority
to control a person (including corporations, partnerships, and similar entities)
from one entity to another.

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      "COMPETING BUSINESS" means a business that competes with APSH or its
subsidiaries in managed behavioral health.

      "CONTROL" means the possession, directly or indirectly, of the power to
cause the direction of the management and policies of a person (including
corporations, partnerships and similar entities), through ownership of more than
fifty percent (50%) of the voting securities or the right to elect more than 50%
of the Board of Directors of a party.

      "INITIAL PUBLIC OFFERING" means the effective date of an S-1 registration
statement (or any comparable successor form) with respect to the firm commitment
underwriting of the first public offering of equity securities of APSH
registered under the Securities Act.

      "PERMITTED TRANSFEREE" means Blue Cross and Blue Shield of Montana
("BCBSMT"), provided that (i) at the time of the transfer BCBSMT does not own,
operate, manage or control a Competing Business (except for such business(es)
that it owned, operated, managed, or controlled as of the date of execution of
this Agreement) and (ii) BCBSMT assumes all of CBMI's obligations under the
Stock Purchase Agreement and this Agreement.

      "REGISTER," "REGISTERED," and "REGISTRATION" refer to a registration
effected by preparing and filing a registration statement in compliance with the
Securities Act, and the declaration or ordering of effectiveness of such
registration statement or document.

      "REGISTRABLE SECURITIES" means the Buyer's Shares as held by CBMI or the
Permitted Transferee. Notwithstanding the foregoing, Registrable Securities
shall not include any securities (i) sold by a person to the public either
pursuant to a registration statement or Rule 144, or (ii) sold in a private
transaction in which the transferor's rights under Article 3 of this Agreement
are not assigned.

      "REGISTRATION EXPENSES" shall mean all expenses incurred by APSH in
complying with, without limitation, all registration and filing fees, printing
expenses, fees and disbursements of counsel for APSH, reasonable fees and
disbursements of a single special counsel to all holders of registration rights
participating in the applicable offering, blue sky fees and expenses and the
expense of any special audits incident to or required by any such registration
(but excluding the compensation of regular employees of APSH which shall be paid
in any event by APSH).

      "SECURITIES ACT" shall mean the Securities Act of 1933, as amended.

      "SELLING EXPENSES" shall mean all underwriting discounts, selling
commissions and stock transfer taxes, if any, applicable to the sale.

      "SEC" or "COMMISSION" means the Securities and Exchange Commission.

2. RESTRICTIONS ON TRANSFER

      2.1   DISPOSITIONS TO PERMITTED TRANSFEREES. Until the consummation of
APSH's Initial Public Offering, CBMI agrees not to make any disposition of all
or any portion of the Buyer's Shares unless:


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            (i) Such disposition is a disposition of all, but not less than all,
of such Buyer's Shares to the Permitted Transferee that has agreed in writing
for the benefit of APSH to be bound by this Agreement (and references herein to
"CBMI" shall be interpreted in the alternative to mean such transferee);

            (ii) There is then in effect a registration statement under the
Securities Act covering such proposed disposition and such disposition is made
in accordance with such registration statement; or

            (iii) CBMI shall have (A) notified APSH of the proposed disposition
and shall have furnished APSH with a detailed statement of the circumstances
surrounding the proposed disposition, and (B) delivered to APSH an opinion of
CBMI's counsel that such disposition will not require registration of such
shares under the Securities Act, provided that such opinion is determined to be
reasonable by APSH and its counsel.

      2.2   CERTIFICATES.

            2.2.1 Each certificate representing Registrable Securities shall
(unless otherwise permitted by the provisions of this Agreement) be stamped or
otherwise imprinted with a legend substantially similar to the following (in
addition to any legend required under applicable state securities laws):

            (i)   THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED
                  UNDER THE SECURITIES ACT OF 1933 (THE "ACT") OR UNDER ANY
                  APPLICABLE STATE SECURITIES LAWS AND MAY NOT BE OFFERED, SOLD
                  OR OTHERWISE TRANSFERRED, ASSIGNED, PLEDGED OR HYPOTHECATED IN
                  THE ABSENCE OF REGISTRATION OR AN EXEMPTION THEREFROM UNDER
                  SUCH ACT AND SUCH LAWS; and,

            (ii)  THE SECURITIES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS OF
                  A SHAREHOLDER'S RIGHTS AGREEMENT DATED OCTOBER 18, 1999
                  BETWEEN THE REGISTERED HOLDER AND APSH AND MAY NOT BE OFFERED,
                  SOLD, OR OTHERWISE TRANSFERRED, ASSIGNED, PLEDGED OR
                  HYPOTHECATED EXCEPT IN STRICT COMPLIANCE WITH THE TERMS OF
                  SUCH AGREEMENT.

            2.2.2 After APSH's Initial Public Offering, APSH shall reissue
promptly unlegended certificates at the request of any holder thereof if the
holder shall have obtained an opinion of counsel (which counsel may be counsel
to APSH) reasonably acceptable to APSH to the effect that the securities
proposed to be disposed of may lawfully be so disposed of without registration,
qualification or legend.


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            2.2.3 As to any Registrable Securities sold pursuant to a public
offering registered under the Securities Act or sold in accordance with Section
2.1 (ii) or (iii) above, APSH shall promptly reissue unlegended certificates at
the request of any holder thereof.

3. REGISTRATION RIGHTS

      3.1   REGISTRATION REQUEST AND JOINDER

            REQUEST FOR REGISTRATION. In case APSH shall receive from CBMI or
the Permitted Transferee a written request that APSH effect registration of all
or a portion of the Registrable Securities under the Securities Act, APSH will,
as soon as practicable, use its Best Efforts to effect such registration
(including, without limitation, appropriate registration under applicable blue
sky or other state securities laws and appropriate compliance with applicable
regulations issued under the Securities Act and any other governmental
requirements or regulations) as may be so requested and as may be reasonably
required to permit or facilitate the sale and distribution of all or such
portion of such Registrable Securities as are specified in such request;
PROVIDED, HOWEVER, that APSH shall be entitled to postpone for up to 90 days the
commencement of such registration process if the Board of Directors of APSH
determines, in its good faith reasonable judgment, that such registration
contemplated thereby would materially interfere with, or require premature
disclosure of, any financing, acquisition, or reorganization involving APSH or
any of its subsidiaries and APSH promptly gives notice to CBMI of such
determination, and further provided that APSH shall not be obligated to take any
action to effect any such registration pursuant to this Section 3.1.1:

            (i)   Prior to the first anniversary of the completion of the
                  Initial Public Offering of APSH;

            (ii)  If APSH has effected one such registration of all of the
                  Registrable Securities pursuant to this section 3.1.1, such
                  registration has been declared or ordered effective, and such
                  registration has not been terminated, withdrawn or stopped
                  prior to the time period set forth in section 3.4.1 below;

            (iii) If the registration or qualification requested does not relate
                  to at least fifty percent (50%) of all Registrable Securities
                  held by CBMI or the Permitted Transferee; or

            (iv)  If APSH provides an opinion from its counsel that the
                  Registrable Securities are freely tradable and such opinion
                  specifies the grounds upon which it is rendered, provided that
                  such opinion is determined to be reasonable by CBMI (or by the
                  Permitted Transferee, as applicable) and its counsel.

      Subject to the foregoing clauses (i) through (iv), APSH shall file a
registration statement covering the Registrable Securities so requested to be
registered as soon as practicable after receipt of the request of CBMI or the
Permitted Transferee.



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            3.1.2  JOINDER OF APSH AND OTHER SECURITY HOLDERS.

        In any registration requested pursuant to this Section 3.1, APSH shall
be entitled to register securities for sale for its own account or for the
account of any other holder or holders of APSH securities with rights to include
their securities in such registration.

      3.2   SECONDARY OFFERINGS/PIGGYBACK REGISTRATIONS. Provided that APSH's
Initial Public Offering has occurred, APSH shall notify CBMI in writing at least
thirty (30) days prior to the filing of any registration statement, subsequent
to the registration statement for such Initial Public Offering, under the
Securities Act for purposes of a public offering of common stock of APSH
(including, but not limited to registration statements relating to secondary
offerings of the securities of APSH, but excluding registration statements
relating to employee benefit plans, business acquisitions, and corporate
reorganizations). The notice shall state the intended method of disposition of
the common stock proposed to be registered by APSH. If desiring to include in
any such registration statement all or any part of its Registrable Securities,
CBMI shall, within fifteen (15) days after the above-described notice from APSH
has been given, provide written notice to APSH of the amount of Registrable
Securities for which registration is requested by CBMI. Subject to the
limitations set forth in Section 3.2.1 below, APSH will use Best Efforts to
include in the registration the amount of Registrable Securities requested by
CBMI. Notwithstanding the foregoing, the parties recognize that APSH may be
precluded or limited from including in such registration the Registrable
Securities, as a result of other existing contracts or agreements to which APSH
is a party or otherwise bound.

            3.2.1 UNDERWRITING. If the registration statement for which APSH
gives notice under this Section 3.2 is for an underwritten offering, CBMI's
right to be included in a registration pursuant to this Section 3.2 shall be
conditioned upon CBMI's participation in such underwriting and the inclusion of
CBMI's Registrable Securities in the underwriting to the extent provided herein.
If proposing to distribute its Registrable Securities through such underwriting,
CBMI shall enter into an underwriting agreement in customary form with the
underwriter or underwriters selected for such underwriting. Notwithstanding any
other provision of the Agreement, if the underwriter advises APSH in writing (a
copy of which shall be furnished to CBMI) that, in its opinion, the distribution
of the number of securities proposed to be included in the registration would
materially and adversely affect the distribution of APSH common stock, then APSH
will include in such registration: first, the common stock APSH proposes to
offer for sale; second, any stock in APSH entitled to superior registration
rights under existing agreements between holders of such stock and APSH, as set
forth on the attached Schedule I; third, the Registrable Securities and the
stock of any shareholder of APSH holding similar registration rights on a pro
rata basis; and fourth, the stock of any other shareholder of APSH on a pro rata
basis. No such reduction shall reduce the securities being offered by APSH for
its own account to be included in the registration and underwriting.

            3.2.2 RIGHT TO TERMINATE REGISTRATION. APSH shall have the right to
terminate or withdraw any registration initiated by it under this Section 3.2
prior to the effectiveness of such registration whether or not CBMI has elected
to include securities in such registration.

      3.3   EXPENSES OF REGISTRATION. All Registration Expenses incurred in
connection with any registration, qualification or compliance pursuant to this
Section 3 shall be borne by


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APSH. All Selling Expenses incurred in connection with any registrations
hereunder, shall be borne by the holders of the securities so registered pro
rata on the basis of the number of shares so registered.

      3.4   OBLIGATIONS OF APSH. Whenever required to effect the registration of
any Registrable Securities, APSH shall use its Best Efforts to:

            3.4.1 Prepare and file with the SEC a registration statement with
respect to such Registrable Securities and use its Best Efforts to cause such
registration statement to become effective, and keep such registration statement
effective for one hundred eighty (180) days or, if earlier, until the
distribution related thereto is completed.

            3.4.2 Prepare and file with the SEC such amendments and supplements
to such registration statement and the prospectus used in connection with such
registration statement as may be necessary to comply with the provisions of the
Securities Act with respect to the disposition of all securities covered by such
registration statement.

            3.4.3 Furnish to CBMI such number of copies of the registration
statement, any pre-effective or post-effective amendment thereto, the
prospectus, including a preliminary prospectus and any amendment or supplement
to the prospectus, in conformity with the requirements of the Securities Act,
and such other documents as CBMI may reasonably request in order to facilitate
the disposition of Registrable Securities owned by CBMI.

            3.4.4 Register and qualify the securities covered by such
registration statement under such other securities or Blue Sky laws of such
jurisdictions as shall be reasonably requested by CBMI, provided that APSH shall
not be required in connection therewith or as a condition thereto to qualify to
do business or to file a general consent to service of process (as opposed to a
consent to service of process in connection with state securities laws) in any
such states or jurisdictions.

            3.4.5 In the event of any underwritten public offering, enter into
and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter(s) of such offering. If
participating in such underwriting, CBMI shall also enter into and perform its
obligations under such an agreement.

            3.4.6 Notify CBMI at any time when a prospectus relating to the
registration of the Registrable Securities is required to be delivered under the
Securities Act of the happening of any event as a result of which the prospectus
included in such registration statement, as then in effect, includes an untrue
statement of a material fact or omits to state a material fact required to be
stated therein or necessary to make the statements therein not misleading in the
light of the circumstances then existing.

            3.4.7 Furnish on the date that the Registrable Securities are
delivered to the underwriters for sale, if such securities are being sold
through underwriters, or, if such securities are not being sold through
underwriters, on the date that the registration statement with respect to such
securities becomes effective: (i) an opinion, dated as of such date, of the
counsel representing APSH for the purposes of such registration, in form and
substance as is customarily given to underwriters in an underwritten public
offering, addressed to the underwriters, if any,


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and to the holders of the Registrable Securities requesting registration of the
registrable securities; and (ii) a letter dated as of such date, from the
independent certified public accountants of APSH, in form and substance as is
customarily given by independent certified public accountants to underwriters in
an underwritten public offering addressed to the underwriters, if any, and if
permitted by applicable accounting standards, to the holders requesting
registration of Registrable Securities.

            3.4.8 APSH shall keep CBMI reasonably informed throughout the
registration process, including without limitation notifying CBMI promptly and
confirming such advice in writing promptly thereafter:

            (i)   when the registration statement, the prospectus or any
                  prospectus supplement related thereto or post-effective
                  amendment to the registration statement has been filed, and,
                  with respect to the registration statement or any
                  post-effective amendment thereto, when the same has become
                  effective with the SEC and with those states where
                  registration or qualification was requested;

            (ii)  of any request by the SEC for amendments or supplements to the
                  registration statement or the prospectus or for additional
                  information;

            (iii) of the issuance by the SEC of any stop order suspending the
                  effectiveness of the registration or the initiation of any
                  proceedings for that purpose; and

            (iv)  of the receipt by APSH of any notification with respect to the
                  suspension of the qualification of any Registrable Securities
                  for sale under the securities or blue sky laws of any
                  jurisdiction or the initiation or threat of any proceeding for
                  such purpose.

      3.5   TERMINATION OF REGISTRATION RIGHTS. All registration rights granted
under this Article 3 shall terminate and be of no further force and effect: (i)
five (5) years after the closing of the Stock Purchase Agreement; or (ii) if
CBMI or the Permitted Transferee acquires a Competing Business; or (iii) if
CBMI's rights under this Agreement are transferred by CBMI to anyone other than
the Permitted Transferee or are transferred by the Permitted Transferee to a
third party by contract, merger, or otherwise by operation of law.

      3.6   DELAY OF REGISTRATION; FURNISHING INFORMATION.

            3.6.1 CBMI shall not have any right to obtain or seek an injunction
restraining or otherwise delaying any such registration as the result of any
controversy that might arise with respect to the interpretation or
implementation of this Article 3.

            3.6.2 It shall be a condition precedent to the obligations of APSH
to take any action pursuant to this Article 3 that CBMI shall furnish to APSH
such information regarding itself, the Registrable Securities it holds, and the
intended method of disposition of such securities as shall be required to effect
the registration of the Registrable Securities.

      3.7   INDEMNIFICATION. In the event any Registrable Securities are
included in a registration statement under this Article 3:


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            3.7.1 To the extent permitted by law, APSH will indemnify and hold
harmless CBMI, each of its directors, each of its officers, any underwriter (as
defined in the Securities Act) for CBMI and each person, if any, who controls
CBMI or such underwriter within the meaning of the Securities Act or the
Securities Exchange Act of 1934, as amended (the "1934 Act"), against any
losses, claims, damages or liabilities (joint or several) to which they may
become subject under the Securities Act, the 1934 Act or other federal or state
law, insofar as such losses, claims, damages or liabilities (or actions in
respect thereof) arise out of or are based upon any of the following statements,
omissions or violations (collectively a "Violation") by APSH: (i) any untrue
statement or alleged untrue statement of a material fact contained in such
registration statement, including any preliminary prospectus or final prospectus
contained therein or any amendments or supplements thereto, (ii) the omission or
alleged omission to state therein a material fact required to be stated therein,
or necessary to make the statements therein not misleading, or (iii) any
violation or alleged violation by APSH of the Securities Act, the 1934 Act, any
state securities law or any rule or regulation promulgated under the Securities
Act, the 1934 Act or any state securities law in connection with the offering
covered by such registration statement; and APSH will reimburse CBMI, its
partners, officers or directors, underwriter or controlling person for any legal
or other expenses reasonably incurred by them in connection with investigating
or defending any such loss, claim, damage, liability or action; provided
however, that the indemnity agreement contained in this Section 3.7.1 shall not
apply to amounts paid in settlement of any such loss, claim, damage, liability
or action if such settlement is effected without the consent of APSH (which
consent shall not be unreasonably withheld), nor shall APSH be liable in any
such case for any such loss, claim, damage, liability or action to the extent
that it arises out of or is based upon a Violation which occurs in reliance upon
and in conformity with written information furnished for use in connection with
such registration by CBMI or its partners, officers, directors, underwriter or
controlling person.

            3.7.2 To the extent permitted by law, CBMI will indemnify and hold
harmless APSH, each of its directors, each of its officers, each person, if any,
who controls APSH within the meaning of the Securities Act, any underwriter and
any other shareholder selling securities under such registration statement or
any of such other shareholder's partners, directors or officers or any person
who controls such shareholder, against any losses, claims, damages or
liabilities (joint or several) to which APSH or any such director, officer,
controlling person, underwriter or other shareholder, or partner, director,
officer or controlling person of such other shareholder may become subject under
the Securities Act, the 1934 Act or other federal or state law, insofar as such
losses, claims, damages or liabilities (or actions in respect thereto) arise out
of or are based upon any Violation, in each case to the extent (and only to the
extent) that such Violation occurs in reliance upon and in conformity with
written information furnished by CBMI under an instrument duly executed by CBMI
for use in connection with such registration; and CBMI will reimburse any legal
or other expenses reasonably incurred by APSH or any such director, officer,
controlling person, underwriter or other shareholder, or partner, officer,
director or controlling person of such other shareholder in connection with
investigating or defending any such loss, claim, damage, liability or action if
it is judicially determined that there was such a Violation; provided, however,
that the indemnity agreement contained in this Section 3.7.2 shall not apply to
amounts paid in settlement of any such loss, claim, damage, liability or action
if such settlement is effected without the consent of CBMI (which consent shall
not be unreasonably


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withheld or delayed); provided further, that in no event shall any indemnity
under this Section 3.7 exceed the gross proceeds from the offering received by
CBMI.

            3.7.3 Promptly after receipt by an indemnified party under this
Section 3.7 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 3.7, deliver to
the indemnifying party a written notice of the commencement thereof, and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, to assume the defense thereof with counsel mutually
satisfactory to the parties; provided, however, that an indemnified party shall
have the right to retain its own counsel, with the fees and expenses to be paid
by the indemnifying party, if representation of such indemnified party by the
counsel retained by the indemnifying party would be inappropriate due to actual
or potential differing interests between such indemnified party and any other
party represented by such counsel in such proceeding. The failure to deliver
written notice to the indemnifying party within a reasonable time of the
commencement of any such action, if materially prejudicial to its ability to
defend such action, shall relieve such indemnifying party of any liability to
the indemnified party under this Section 3.7, but the omission so to deliver
written notice to the indemnifying party will not relieve it of any liability
that it may have to any indemnified party otherwise than under this Section 3.7.

            3.7.4 If the indemnification provided for in this Section 3.7 is
held by a court of competent jurisdiction to be unavailable to an indemnified
party with respect to any losses, claims, damages or liabilities referred to
herein, the indemnifying party, in lieu of indemnifying such indemnified party
thereunder, shall to the extent permitted by applicable law contribute to the
amount paid or payable by such indemnified party as a result of such loss,
claim, damage or liability in such proportion as is appropriate to reflect the
relative fault of the indemnifying party on the one hand and of the indemnified
party on the other in connection with the Violation(s) that resulted in such
loss, claim, damage or liability, as well as any other relevant equitable
considerations. The relative fault of the indemnifying party and of the
indemnified party shall be determined by a court of law by reference to, among
other things, whether the untrue or alleged untrue statement of a material fact
or the omission to state a material fact relates to information supplied by the
indemnifying party or by the indemnified party and the parties' relative intent,
knowledge, access to information and opportunity to correct or prevent such
statement or omission; provided, that in no event shall any contribution by CBMI
hereunder exceed the proceeds from the offering received by CBMI.

            3.7.5 The foregoing indemnity agreements of APSH and CBMI are
subject to the condition that, insofar as they relate to any Violation made in a
preliminary prospectus but eliminated or remedied in the amended prospectus on
file with the SEC at the time the registration statement in question becomes
effective or the amended prospectus filed with the SEC pursuant to SEC Rule
424(b) (the "FINAL PROSPECTUS"), such indemnity agreement shall not inure to the
benefit of any person if a copy of the Final Prospectus was furnished to the
indemnified party and was not furnished to the person asserting the loss,
liability, claim or damage at or prior to the time such action is required by
the Securities Act.


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            3.7.6 The obligations of APSH and CBMI under this Section 3.7 shall
survive the completion of any offering of Registrable Securities pursuant to a
registration statement or otherwise.

      3.8   ASSIGNMENT OF REGISTRATION RIGHTS. The rights regarding Registrable
Securities pursuant to Article 3 may be assigned by CBMI to a Permitted
Transferee.

      3.9   "MARKET STAND-OFF" AGREEMENT. If requested by APSH or a
representative of the underwriters of common stock (or other securities) of
APSH, CBMI shall not sell or otherwise transfer or dispose of any common stock
(or other securities) of APSH held by CBMI for a period specified by the
representative of the underwriters, not to exceed one hundred eighty (180) days
following the effective date of the registration statement for the Initial
Public Offering of APSH filed under the Securities Act (the "Effective Date").
APSH may impose stop-transfer instructions with respect to the shares of common
stock (or other securities) subject to the foregoing restriction until the end
of said one hundred eighty (180) day period.

      3.10  RULE 144 REPORTING. With a view to making available to CBMI the
benefits of certain rules and regulations of the SEC which may permit the sale
of the Registrable Securities to the public without registration, APSH agrees to
use its best efforts to:

            3.10.1 Make and keep public information available, as those terms
are understood and defined in SEC Rule 144 or any similar or analogous rule
promulgated under the Securities Act, at all times after the effective date of
the Initial Public Offering;

            3.10.2 File with the SEC, in a timely manner, all reports and other
documents required of APSH under the Securities Act and the Securities Exchange
Act of 1934, as amended (the "Exchange Act") so long as APSH is subject to the
Exchange Act; and

            3.10.3 So long as CBMI owns any Registrable Securities, furnish to
CBMI forthwith upon request: a written statement by APSH as to its compliance
with the reporting requirements of said Rule 144 of the Securities Act, and of
the Exchange Act (at any time after it has become subject to such reporting
requirements); a copy of the most recent annual or quarterly report of APSH; and
such other reports and documents as CBMI may reasonably request in availing
itself of any rule or regulation of the SEC allowing it to sell any such
securities without registration.

      3.11  NO FURTHER GRANTS OF RIGHTS. During the term of this Agreement, APSH
shall not grant or otherwise provide, including, without limitation, amendment
of existing registration rights, any registration rights for securities of APSH
to any other party which would be superior or equal to the registration rights
granted to CBMI herein. Notwithstanding the foregoing, APSH will be entitled to
request CBMI to permit APSH to grant or otherwise provide to another party
registration rights equal to those granted to CBMI, which request shall not be
unreasonably denied by CBMI.


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4. CHANGE OF CONTROL AND PUT/CALL RIGHTS

      4.1   CHANGE OF CONTROL OF APSH. In the event that there is a Change in
Control of APSH, then CBMI will have the right, but not the obligation, to sell
its Buyer's Shares to APSH, on the same terms and conditions, including price
per share and form of consideration, as that obtained by the holders of a
majority of APSH's common stock. If CBMI exercises this right, APSH shall buy
CBMI's Buyer's Shares on the terms stated in this Section 4.1.

      4.2   PUT/CALL RIGHTS.

            4.2.1 PUT/CALL RIGHTS. If the Buyer's Shares have not been sold
pursuant to Section 4.1 or pursuant to a registration within five (5) years
after the closing of the Stock Purchase Agreement (the "Trigger Date"), then
CBMI will have the right to put the Buyer's Shares to APSH and to require APSH
to purchase all of the Buyer's Shares then owned by CBMI for cash on the terms
set forth in this Section 4.2. This put right must be exercised by CBMI, if at
all, within sixty (60) days after the Trigger Date by written notice of such
exercise to APSH (the "Exercise Date"). If CBMI or a Permitted Transferee
acquires or otherwise comes to control a Competing Business, then APSH will have
the right to call the Buyer's Shares for cash, and to require CBMI or the
Permitted Transferee to sell all of Buyer's Shares then owned by such parties on
the terms set forth in this Section 4.2. For purposes of this call provision,
the "Trigger Date" shall be the date of acquisition of the Competing Business,
and the "Exercise Date" shall be sixty (60) days after APSH receives notice of
the consummation of such acquisition.

            4.2.2 PURCHASE PRICE. The purchase price to be paid for the Buyer's
Shares to be purchased by APSH under this Section 4.2 shall be equal to the per
share fair market value determined as provided herein (the "Price"). The Price
shall be determined without regard to any restrictions on transferability of the
stock or the minority status of the stock.

            4.2.3 DETERMINATION OF PRICE. In the event that the Buyer's Shares
are publicly traded, the Price shall be determined by averaging the closing
price of the Buyer's Shares for the thirty (30) days prior to the put/call on
them. If the Buyer's shares are not publicly traded, and if CBMI and APSH are
able to reach mutual agreement as to the Price, then such agreed Price shall
govern. If CBMI and APSH cannot agree on a Price within fifteen (15) days after
the Exercise Date, the Price shall be determined by an independent appraiser
appointed by CBMI and APSH within thirty (30) days after the Exercise Date. If
CBMI and APSH cannot agree on an appraiser within such period, the Price shall
be determined jointly by an independent appraiser appointed by CBMI and an
independent appraiser appointed by APSH, each to be appointed within forty-five
(45) days after the Exercise Date. If the two appraisers are unable to agree on
a Price within forty-five (45) days after their appointment, they shall (within
60 days after their appointment) select a third independent appraiser who shall
determine (within 45 days after his or her appointment) the Price by arriving at
a valuation either equal to that determined by one of the initial two appraisers
or intermediate between such two initial valuations. If the higher of the values
determined by the initial two appraisers is not in excess of 115% of the value
determined by the other appraiser, or if the two initial appraisers are unable
to agree upon a third appraiser, the appraisers shall be deemed to have agreed
upon a Price equal to the average of the two determinations.


                                      -11-
<PAGE>

            4.2.4 COST OF APPRAISAL. CBMI and APSH shall each bear the cost and
expenses of the appraiser it appoints, and each shall bear one-half of the cost
and expenses of the third appraiser or the sole appraiser if only one is
appointed.

            4.2.5 CLOSING. Closing of the sale of the Buyer's Shares from CBMI
to APSH shall be held within thirty (30) days after determination of the Price.
At closing, APSH shall pay the Price in cash to CBMI, and CBMI shall execute a
stock transfer power for the Buyer's Shares to APSH which shall be delivered
together with the certificates for the Buyer's Shares to APSH.

      4.3   TERMINATION OF RIGHTS. All rights provided under this Article 4 to
CBMI shall terminate and be of no further force and effect in the event that (i)
CBMI or the Permitted Transferee acquires a Competing Business; or (ii) if
rights under this Agreement are transferred by CBMI to anyone other than the
Permitted Transferee or by the Permitted Transferee to any third party by
contract, merger, or otherwise by operation of law.

5. CONFIDENTIALITY OF RECORDS.

      5.1   TREATMENT OF CONFIDENTIAL INFORMATION. CBMI agrees not to use
Confidential Information (as hereinafter defined) of APSH for any purpose except
to evaluate and monitor its equity investment in APSH. Except as permitted under
Section 5.2 below, CBMI shall undertake to treat such Confidential Information
in a manner consistent with the treatment of its own information of such
proprietary nature and agrees that it shall protect the confidentiality of the
Confidential Information in the same manner which it protects its own
confidential information. Each transferee of CBMI who received Confidential
Information shall agree to be bound by such provisions. For purposes of this
Section, "Confidential Information" means any information, technical data, or
know-how, including, but not limited to, APSH's research, products, software,
services, development, inventions, processes, designs, drawings, engineering,
marketing, or finances, disclosed by APSH to CBMI in writing or disclosed orally
with a prompt written confirmation that such information is Confidential
Information.

      5.2   EXCLUSION OF CERTAIN INFORMATION. Confidential Information does not
include information, technical data or know-how which (i) is in CBMI's
possession at the time of disclosure as shown by CBMI's files and records
immediately prior to the time of disclosure; (ii) before or after it has been
disclosed to CBMI, it is part of the public knowledge or literature, not as a
result of any action or inaction of CBMI; (iii) is disclosed to CBMI on a
non-confidential basis by a third party having a legal right to make such
disclosure; or (iv) is approved for release by written authorization of APSH.

      5.3   APPLICABILITY OF ARTICLE 5. The provisions of this Article 5 shall
not apply (i) to the extent that CBMI is required to disclose Confidential
Information pursuant to any law, statute, rule or regulation or any order of any
court or jurisdiction process or (with written notice to APSH) pursuant to any
direction, request or requirement (whether or not having the force of law but if
not having the force of law being of a type with which institutional investors
in the relevant jurisdiction are accustomed to comply) of any self-regulating
organization or any governmental, fiscal, monetary or other authority; (ii) to
the disclosure of Confidential Information to CBMI's employees, counsel,
accountants or other professional advisors to the extent necessary for the
performance of their duties; or (iii) to the extent that CBMI needs to


                                      -12-
<PAGE>

disclose Confidential Information for the protection of any of CBMI's rights or
interest against APSH, whether under this Agreement or otherwise.

6. REMEDIES

      6.1   REMEDIES. If either party to this Agreement fails to perform its
obligations hereunder, then the other party may, at its option, pursue any
remedies available to it at law or in equity, including without limitation a
suit for specific performance or for an injunction.

      6.2   ATTORNEY FEES. If either party defaults in its performance hereunder
and the other party employs an attorney because of such default, the defaulting
party agrees to pay, on demand, all costs, charges and expenses, including
reasonable attorney fees, incurred at any time by the other party because of the
default.

7. MISCELLANEOUS.

      7.1   GOVERNING LAW. This Agreement shall be governed by and construed
under the laws of the State of Delaware as applied to agreements among Delaware
residents entered into and to be performed entirely within Delaware.

      7.2   SURVIVAL. All statements as to factual matters contained in any
certificate or other instrument delivered by or on behalf of APSH pursuant
hereto in connection with the transactions contemplated hereby shall be deemed
to be representations and warranties by APSH hereunder solely as of the date of
such certificate or instrument.

      7.3   SUCCESSORS AND ASSIGNS; INTERPRETATION. Except as otherwise
expressly provided herein, the provisions hereof shall inure to the benefit of,
and be binding upon, the successors and assigns of the parties hereto and shall
inure to the benefit of and be enforceable by each Permitted Transferee and such
transferee shall be deemed "CBMI" for purposes of interpreting this Agreement.

      7.4   SEPARABILITY. In case any provision of the Agreement shall be
invalid, illegal, or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

      7.5   AMENDMENT AND WAIVER. Except as otherwise expressly provided, this
Agreement may be amended or modified only upon the written consent of APSH and
CBMI.

      7.6   NOTICES. Unless otherwise specified herein, all notices, requests
and other communications to any Party shall be in writing (including telexes,
telecopies, facsimile transmissions, and similar writings) and shall be given to
such Party at its address or telecopier number set forth below or such other
address or telecopier number as such Party may hereafter specify for that
purpose by notice to the other Parties.


                                      -13-
<PAGE>

            If to CBMI:       Combined Benefits Management, Inc.
                              Attn: Ronald King
                              560 North Park Avenue
                              Helena, MT 59601

            With a Copy to:   Terry Cosgrove, Esq.
                              Crowley, Haughey, Hanson, Toole & Dietrich
                              PO Box 797
                              Helena, MT 59624

            If to APSH:       American Psych Systems Holdings, Inc.
                              Attn: Kenneth A. Kessler, M.D.
                              6705 Rockledge Drive, Suite 200
                              Bethesda, MD 20817

            With a Copy to:   Brian D. Gradle, Esq.
                              Epstein Becker & Green P.C.
                              1227 25th Street, N.W.
                              Washington, D.C. 20037

Each such notice, request or other communication shall be effective (a) if given
by telecopier, when such telecommunication is transmitted and confirmation of
receipt obtained, (b) if given by mail, upon receipt, or (c) if given by any
other means, when delivered at the address specified in this Section.

      7.7   ATTORNEYS' FEES. In the event that any dispute among the parties to
this Agreement should result in litigation, the prevailing party in such dispute
shall be entitled to recover from the losing party its reasonable fees and
expenses of attorneys and accountants in connection therewith.

      7.8   TITLES AND SUBTITLES. The titles of the sections and subsections of
this Agreement are for convenience of reference only and are not to be
considered in construing this Agreement.

      7.9   COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

      7.10  REFERENCES TO CBMI. All references to CBMI in this Agreement shall
also include the Permitted Transferee if it becomes the holder of the
Registrable Securities.




                                      -14-
<PAGE>

      IN WITNESS WHEREOF, the parties hereto have executed this Shareholder's
Rights Agreement as of the date set forth in the first paragraph hereof.



      AMERICAN PSYCH SYSTEMS HOLDINGS, INC.

      BY:    /s/ Stephen DaRe
            ------------------------------------------

      NAME:  Stephen DaRe
            ------------------------------------------

      TITLE: CFO
            ------------------------------------------



      COMBINED BENEFITS MANAGEMENT, INC.

      BY:    /s/ Terry Screnar
            ------------------------------------------

      NAME:  Terry Screnar
            ------------------------------------------

      TITLE: President & CEO
            ------------------------------------------




                                      -15-
<PAGE>



                                   SCHEDULE I



      1.    Registration Rights Agreement, dated March 30, 1994, made by
American Psych Systems, Inc. for the benefit of the Investors listed on Schedule
I thereto.

      2.    Registration Rights Agreement, dated March 30, 1994, made by
American Psych Systems, Inc. for the benefit of KBL Healthcare, Inc. and its
designees listed on Schedule I thereto.

      3.    Registration Rights Agreement, dated February 3, 1995, made by
American Psych Systems, Inc. for the benefit of the Investors listed on Schedule
I thereto.

      4.    Registration Rights Agreement, dated February 3, 1995, made by
American Psych Systems, Inc. for the benefit of KBL Healthcare, Inc. and its
designees listed on Schedule I thereto.

      5.    Second Amended and Restated Registration Rights Agreement, dated
June 17, 1996, by and between American Psych Systems, Inc. and the Investors
named therein.

      6.    Amendment to the Second Amended and Restated Registration Rights
Agreement, dated September 26, 1997.

      7.    Registration Rights Agreement, dated September 26,1997, among
American Psych Systems Holdings, Inc., Can Partners Investments IV, LLC, Nazem &
Company IV, L.P. and the holder of securities of the Company.

      8.    Amendment to Registration Rights Agreement, dated December 23, 1998.

      9.    Warrantholders Rights Agreement, dated December 23, 1998, by and
between American Psych Systems Holdings, Inc., NationsCredit Commercial
Corporation and the Investors named therein.