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Exhibit 3.21
                            ARTICLES OF INCORPORATION
                                       OF
                             CORNERSTONE CARE, INC.

         The undersigned, a natural person of the age of eighteen years or more,
acting as incorporator of this corporation under the Colorado Corporation Act,
adopts the following Articles of Incorporation for this corporation:

                                    ARTICLE I
                               NAME OF CORPORATION

         The name of the corporation is Cornerstone Care, Inc.

                                   ARTICLE II
                             DURATION OF CORPORATION

         The period of its duration is perpetual.

                                   ARTICLE III
                               PURPOSES AND POWERS

         The purposes and powers of the corporation shall be as follows:

         The purpose of the corporation shall be to transact all lawful business
for which corporations may be incorporated pursuant to the Colorado Business
Corporation Act, as amended. The corporation shall have the power to do all and
everything necessary, suitable and proper for the accomplishment of its purpose.

                                   ARTICLE IV
                                     CAPITAL

         The aggregate number of shares the corporation shall have authority to
issue is 100,000 shares of common stock.

                                    ARTICLE V
                                     VOTING

         Cumulative voting shall not be allowed.

                                   ARTICLE VI
                               PRE-EMPTIVE RIGHTS

         The shareholders shall have no pre-emptive rights to acquire additional
shares of the corporation or securities convertible into shares or carrying
stock purchase warrants or privileges.
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                                   ARTICLE VII
                        ADOPTION AND AMENDMENT OF BY-LAWS

         The by-laws of the corporation shall be adopted by its Board of
Directors. The power to alter or amend or repeal the bylaws or adopt new by-laws
shall be vested in the Board of Directors, but the shareholders may also alter,
amend or repeal the by-laws or adopt new by-laws. The by-laws may contain any
provisions for the regulation and management of the affairs of the corporation
not inconsistent with statute or the Articles of Incorporation.

                                  ARTICLE VIII
                           REGISTERED OFFICE AND AGENT

         The address of the initial registered office of the corporation is 2105
Clubhouse Drive, Greeley, Colorado 80634.

         The name of its registered agent at such address is John Filkoski.

         The address of the Corporation's principal office is 2105 Clubhouse
Drive, Greeley, Colorado 80634.

                                   ARTICLE IX
                       DEALINGS OF OFFICERS AND DIRECTORS

         In the absence of fraud, no contract or other transaction between this
corporation and any other corporation or any partnership or association shall be
affected or invalidated by the fact that any director or officer of the
corporation is pecuniary or otherwise interested in or is a director, member or
officer of such other corporation or of such firm, association or partnership or
is a party to or is pecuniary or otherwise interested in such contract or other
transaction or in any way connected with any person or persons, firms,
associations, partnership or corporation pecuniary or otherwise interested
therein, provided that the existence and nature of any such interest, possession
or connection of such director or officer shall be disclosed or shall have been
known to the directors present at any meeting of the Board of Directors at which
action on any such contract or transaction shall have been taken and provided
further that the fact of such relationship is disclosed or known to the
shareholders entitled to vote and they authorize, approve, or ratify the
contract or transaction by vote or written consent and the contract or
transaction is fair and reasonable to the corporation.

         A director of this corporation shall not be personally liable to the
corporation or to its shareholders for monetary damages for breach of fiduciary
duty as a director, except for liability to this corporation or to its
shareholders for monetary damages for (i) any breach of the director's duty of
loyalty to the corporation or to its shareholders; (ii) acts or omissions not in
good faith or which involve intentional misconduct or a knowing violation of law
(iii) acts specified in Section 7-108-403 of the Colorado Business Corporation
Act; or (iv) any transaction from which the director derived an improper
personal benefit.

         If the Colorado Business Corporation Act is hereafter amended to
authorize the further elimination or limitation of the liability of a director,
then the liability of a director of the


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corporation shall be eliminated or limited to the fullest extent permitted by
the Colorado Business Corporation Act, as so amended.

         Any repeal or modification of the foregoing provisions of this Article
Ninth by the shareholders or the corporation shall not affect adversely any
right or protection of a director of the corporation in respect of any acts or
omissions of such director occurring prior to the time of such repeal or
modification.

         Any director may be counted in determining the existence of a quorum
and may vote at any meeting of the Board of Directors of the corporation for the
purpose of authorizing any such contract or transaction with like force and
effect as it he were not so interested, or were not a director, member or
officer of such other corporation, firm, association or partnership.

                                    ARTICLE X
                          INDEMNIFICATION OF DIRECTORS
                         OFFICERS, EMPLOYEES AND AGENTS

         Each director, officer, employee or agent of the corporation (and his
heirs, executors and administrators) shall be indemnified by the corporation
against expenses reasonably incurred by or imposed upon him in connection with
or arising out of any action, suit or proceeding in which he may be involved or
to which he may be made a party by reason of his being or having been a
director, officer, employee or agent of the corporation, or at its request, of
any other corporation of which it is a shareholder or creditor and from which he
is not entitled to be indemnified (whether or not he continues to be a director
or officer at the time of imposing or incurring such expenses), except in
respect of matters as to which he shall be finally adjudged in such action, suit
or proceeding to be liable for negligence or misconduct; or in the event of a
settlement of any such action, suit or proceeding, indemnification shall be
provided only in connection with such matters covered by the settlement as to
which the corporation is advised by counsel that the person to be indemnified
did not commit a breach of duty. In addition to the foregoing right of
indemnification the personal liability of each director of the corporation shall
be eliminated and limited to the full extent permitted by the laws of the State
of Colorado.

                                   ARTICLE XI
                                INITIAL DIRECTORS

         The number of directors constituting the initial Board of Directors is
one and the name and address of the person who is to serve as a director until
the first annual meeting of shareholders or until his successor is elected and
qualified is:

         NAME                                        ADDRESS

         John Filkoski                               2105 Clubhouse Drive
                                                     Greeley, Colorado 80634




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                                   ARTICLE XII
                                  INCORPORATOR

         The name and address of the incorporator is John Filkoski:

         NAME                                        ADDRESS

         John Filkoski                               2105 Clubhouse Drive
                                                     Greeley, Colorado 80634

         DATED at Greeley, Colorado this 8th day of May, 1995.



                                                      /s/ John Filkoski
                                                     -------------------
                                                     John Filkoski


         The undersigned consents to the appointment as the initial registered
agent of Cornerstone Care, Inc.


                                                     /s/ John Filkoski
                                                     -------------------
                                                     John Filkoski



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