EXHIBIT 3.86

                                     CHARTER
                                       OF
                         BHC SIERRA VISTA HOSPITAL, INC.

                  The undersigned person, having capacity to contract and acting
as the incorporator of a corporation under Section 48-12-101 of the Tennessee
Business Corporation Act (the "Act"), adopts the following charter for such
corporation:

                  1.       Name. The name of the corporation is BHC Sierra Vista
Hospital, Inc. (the "Corporation").

                  2.       Registered Office and Registered Agent. The address
of the registered office of the Corporation in Tennessee is 102 Woodmont
Boulevard, Suite 500, Nashville, Davidson County, Tennessee 37205. The
Corporation's registered agent at the registered office is Michael E. Davis.

                  3.       Incorporator. The name and address of the sole
incorporator of the Corporation is William F. Carpenter III, 511 Union Street,
Suite 2100, Nashville, Davidson County, Tennessee 37219.

                  4.       Principal Office. The address of the principal office
of the Corporation is 102 Woodmont Boulevard, Suite 500, Nashville, Davidson
County, Tennessee 37205.

                  5.       Corporation for Profit. The Corporation is for
profit.

                  6.       Authorized Shares. The Corporation shall have
authority, acting by its board of directors, to issue not more than one thousand
(1,000) shares of common stock, each share without par value ("Common Stock").
All shares of Common Stock shall be one and the same class and when issued shall
have equal rights of participation in dividends and assets of the Corporation
and shall be non-assessable. Each outstanding share of Common Stock shall be
entitled to one vote on each matter submitted to a vote at a meeting of
shareholders.

                  7.       Limitation on Directors' Liability.

                  (a) A director of the Corporation shall not be personally
liable to the Corporation or its shareholders for monetary damages for breach of
fiduciary duty as a director, except for liability for (i) any breach of the
director's duty of loyalty to the Corporation or its shareholders, (ii) acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, or (iii) unlawful distributions under Section 48-18-304 of the
Act, as amended from time to time.



                  (b) If the Act is amended to authorize corporate action
further eliminating or limiting the personal liability of directors, then the
liability of a director of the Corporation shall be eliminated or limited to the
fullest extent permitted by the Act, as so amended. Any repeal or modification
of the foregoing by the shareholders shall not adversely affect any right or
protection of a director of the Corporation existing at the time of such repeal
or modification.

                  8.       Indemnification.

                  (a) The Corporation shall indemnify, and upon request shall
advance expenses to, in the manner and to the full extent permitted by law, any
officer or director (or the estate of any such person) who was or is a party to,
or is threatened to be made a party to, any threatened, pending or completed
action, suit or proceeding, whether civil, criminal, administrative,
investigative or otherwise, by reason of the fact that such person is or was a
director or officer of the Corporation, or is or was serving at the request of
the Corporation as a director, officer, partner, trustee or employee of another
corporation, partnership, joint venture, trust or other enterprise (an
"indemnitee"). The Corporation may, to the full extent permitted by law,
purchase and maintain insurance on behalf of any such person against any
liability which may be asserted against him or her. To the full extent permitted
by law, the indemnification and advances provided for herein shall include
expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement. The indemnification provided herein shall not be deemed to limit the
right of the Corporation to indemnify any other person for any such expenses
(including attorneys' fees), judgments, fines and amounts paid in settlement to
the full extent permitted by law, both as to action in his official capacity and
as to action in another capacity while holding such office. Notwithstanding the
foregoing, the Corporation shall not indemnify any such indemnitee (1) in any
proceeding by the Corporation against such indemnitee; or (2) if a judgment or
other final adjudication adverse to the indemnitee establishes his liability for
(i) any breach of the duty of loyalty to the Corporation or its shareholders,
(ii) acts or omissions not in good faith or which involve intentional misconduct
or a knowing violation of law, or (iii) unlawful distributions under Section
48-18-304 of the Act.

                  (b) The rights to indemnification and advancement of expenses
set forth in paragraph 8(a) above are intended to be greater than those which
are otherwise provided for in the Act, are contractual between the Corporation
and the person being indemnified, his heirs, executors and administrators, and,
with respect to paragraph 8(a), are mandatory, notwithstanding a person's
failure to meet the standard of conduct required for permissive indemnification
under the Act, as amended from time to time. The rights to indemnification and
advancement of expenses set forth in paragraph 8(a) above are nonexclusive of
other similar rights which may be granted by law, this Charter, the bylaws, a
resolution of the board of directors or shareholders of the Corporation, or an
agreement with the Corporation, which means of indemnification and advancement
of expenses are hereby specifically authorized.

                  (c) Any repeal or modification of the provisions of this
paragraph 8, either directly or by the adoption of an inconsistent provision of
this Charter, shall not adversely affect any right or protection set forth
herein existing in favor of a particular individual at the time of

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such repeal or modification. In addition, if an amendment to the Act limits or
restricts in any way the indemnification rights permitted by law as of the date
hereof, such amendment shall apply only to the extent mandated by law and only
to activities of persons subject to indemnification under this paragraph 8 which
occur subsequent to the effective date of such amendment.

                  9.       Express Powers of Board of Directors. In furtherance
of and not in limitation of the powers conferred by statute, the Corporation is
expressly authorized, acting upon the authority of the board of directors and
without the approval of the shareholders, to:

                  (a) Issue shares of any class or series as a share dividend in
respect of shares of the same class or series or any other class or series;

                  (b) Fix or change the number of directors, including an
increase or decrease in the number of directors;

                  (c) Determine, establish or modify, in whole or in part, the
preferences, limitations and relative rights of (i) any class of shares before
the issuance of any shares of that class, or (ii) one or more series within a
class before the issuance of any shares of that series. The board of directors
is further authorized to amend this Charter, without shareholder action, to set
forth such preferences, limitations and relative rights; and

                  (d) Determine, in accordance with law, the method by which
vacancies occurring on the board of directors are to be filled.

                  10.      Removal of Directors for Cause. Directors may be
removed for cause by a vote of a majority of the entire board of directors.

                  11.      Consideration of Non-Shareholder Constituencies. In
considering whether or not to approve, or to recommend that the shareholders
approve, any proposed merger, exchange, tender offer or significant disposition
of assets or to oppose such proposal, the board of directors may consider the
effect of such proposed merger, exchange, tender offer or significant
disposition of assets on the Corporation's employees, customers, suppliers and
the communities in which the Corporation and its subsidiaries operate or are
located.

                                    /s/ William F. Carpenter III
                                    --------------------------------------
                                    William F. Carpenter III
                                    Incorporator

Dated: October 16, 1996

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