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                     AMERICAN MEDICAL SYSTEMS HOLDINGS, INC.

                         Incorporated Under the Laws of

                              the State of Delaware



                                     BY-LAWS
                      (as amended through August 10, 2000)

                                   ARTICLE I
                                    OFFICES.


The registered office of the Corporation in Delaware shall be at 1209 Orange
Street in the City of Wilmington, County of New Castle, in the State of
Delaware, and The Corporation Trust Company shall be the resident agent of this
Corporation in charge thereof. The Corporation may also have such other offices
at such other places, within or without the State of Delaware, as the Board of
Directors may from time to time designate or the business of the Corporation may
require.

                                   ARTICLE II
                                  STOCKHOLDERS.

     Section 1. Annual Meeting. The annual meeting of stockholders for the
election of directors and the transaction of any other business shall be held on
such date, in such city and state and at such time and place as may be
designated by the Board of Directors, and set forth in the notice of such
meeting.

     Section 2. Special Meetings. Special meetings of the stockholders for any
purpose may be called at any time by the Board of Directors, or by the
President, and shall be called by the President at the request of the holders of
a majority of the outstanding shares of capital stock entitled to vote. Special
meetings shall be held at such place or places within or without the State of
Delaware as shall from time to time be designated by the Board of Directors and
stated in the notice of such meeting. At a special meeting no business shall be
transacted and no corporate action shall be taken other than that stated in the
notice of the meeting.

     Section 3. Notice of Meetings. Written notice of the time and place of any
stockholder's meeting, whether annual or special, shall be given to each
stockholder entitled to vote thereat, by personal delivery or by mailing the
same to him at his address as the same appears upon the records of the
Corporation at least ten (10) days but not more than sixty (60) days before the
day of the meeting. Notice of any adjourned meeting need not be given except by
announcement at the meeting





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so adjourned, unless otherwise ordered in connection with such adjournment. Such
further notice, if any, shall be given as may be required by law.

     Section 4. Quorum. Any number of stockholders, together holding at least a
majority of the capital stock of the Corporation issued and outstanding and
entitled to vote, who shall be present in person or represented by proxy at any
meeting duly called, shall constitute a quorum for the transaction of all
business, except as otherwise provided by law, by the Certificate of
Incorporation or by these By-laws.

     Section 5. Adjournment of Meetings. If less than a quorum shall attend at
the time for which a meeting shall have been called, the meeting may adjourn
from time to time by a majority vote of the stockholders present or represented
by proxy and entitled to vote without notice other than by announcement at the
meeting until a quorum shall attend. Any meeting at which a quorum is present
may also be adjourned in like manner and for such time or upon such call as may
be determined by a majority vote of the stockholders present or represented by
proxy and entitled to vote. At any adjourned meeting at which a quorum shall be
present, any business may be transacted and any corporate action may be taken
which might have been transacted at the meeting as originally called.

     Section 6. Voting List. The Secretary shall prepare and make, at least ten
days before every election of directors, a complete list of the stockholders
entitled to vote, arranged in alphabetical order and showing the address of each
stockholder and the number of shares of each stockholder. Such list shall be
open at the place where the election is to be held for said ten days, to the
examination of any stockholder, and shall be produced and kept at the time and
place of election during the whole time thereof, and subject to the inspection
of any stockholder who may be present.

     Section 7. Voting. Each stockholder entitled to vote at any meeting may
vote either in person or by proxy, but no proxy shall be voted on or after three
years from its date, unless said proxy provides for a longer period. Each
stockholder entitled to vote shall at every meeting of the stockholders be
entitled to one vote for each share of stock registered in his name on the
record of stockholders. At all meetings of stockholders all matters, except as
otherwise provided by statute, shall be determined by the affirmative vote of
the majority of shares present in person or by proxy and entitled to vote on the
subject



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matter. Voting at meetings of stockholders need not be by written ballot.

     Section 8. Record Date of Stockholders. The Board of Directors is
authorized to fix in advance a date not exceeding sixty days nor less than ten
days preceding the date of any meeting of stockholders, or the date for the
payment of any dividend, or the date for the allotment of rights, or the date
when any change or conversion or exchange of capital stock shall go into effect,
or a date in connection with obtaining the consent of stockholders for any
purposes, as a record date for the determination of the stockholders entitled to
notice of, and to vote at, any such meeting, and any adjournment thereof, or
entitled to receive payment of any such dividend, or to any such allotment of
rights, or to exercise the rights in respect of any such change, conversion or
exchange of capital stock, or to give such consent, and, in such case, such
stockholders and only such stockholders as shall be stockholders of record on
the date so fixed shall be entitled to such notice of, and to vote at, such
meeting, and any adjournment thereof, or to receive payment of such dividend, or
to receive such allotment of rights, or to exercise such rights, or to give such
consent, as the case may be, notwithstanding any transfer of any stock on the
books of the Corporation, after such record date fixed as aforesaid.

     Section 9. Action Without Meeting. Any action required or permitted to be
taken at any annual or special meeting of stockholders may be taken without a
meeting, without prior notice and without a vote, if a consent or consents in
writing, setting forth the action so taken, shall be signed by the holders of
outstanding stock having not less than the minimum number of votes that would be
necessary to authorize or take such action at a meeting at which all shares
entitled to vote thereon were present and voted and shall be delivered to the
Corporation by delivery to its registered office in the State of Delaware, its
principal place of business, or an officer or agent of the Corporation having
custody of the book in which proceedings of meetings of stockholders are
recorded. Delivery made to the Corporation's registered office shall be by hand
or by certified or registered mail, return receipt requested. Prompt notice of
the taking of the corporate action without a meeting by less than unanimous
written consent shall be given to those stockholders who have not consented in
writing.

     Section 10. Conduct of Meetings. The Chairman of the Board of Directors or,
in his absence the President or any Vice President designated by the Chairman of
the Board, shall preside at all regular or special meetings of stockholders. To
the



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maximum extent permitted by law, such presiding person shall have the power to
set procedural rules, including but not limited to rules respecting the time
allotted to stockholders to speak, governing all aspects of the conduct of such
meetings.

                                  ARTICLE III
                                   DIRECTORS.

     Section 1. Number and Qualifications: The number of directors which shall
constitute the entire Board of Directors shall not be less than one (1) nor more
than nine (9), which number shall be determined from time to time by the Board
of Directors. The Directors shall be divided into three (3) classes, as nearly
equal in number as possible. The term of office of the first class shall expire
at the 2001 annual meeting of the stockholders of the Corporation; the term of
office of the second class shall expire at the 2002 annual meeting of the
stockholders of the Corporation; and the term of office of the third class shall
expire at the 2003 annual meeting of the stockholders of the Corporation. At
each annual meeting of the stockholders after such classification, the number of
directors equal to the number of the class whose term expires on the day of such
meeting shall be elected for a term of three (3) years. Directors shall hold
office until expiration of the terms for which they were elected and qualified.
The directors need not be stockholders.

     Section 2. Election of Directors: The directors shall be elected by the
stockholders at the annual meeting of stockholders.

     Section 3. Duration of Office: The directors chosen at any annual meeting
shall, except as hereinafter provided, hold office until the next annual
election and until their successors are elected and qualify.

     Section 4. Removal and Resignation of Directors: Any director may be
removed from the Board of Directors, but only for cause, by the holders of a
majority of the shares of capital stock entitled to vote, either by written
consent or consents or at any special meeting of the stockholders called for
that purpose, and the office of such director shall forthwith become vacant.

Any director may resign at any time. Such resignation shall take effect at the
time specified therein, and if no time be specified, at the time of its receipt
by the President or



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Secretary. The acceptance of a resignation shall not be necessary to make it
effective, unless so specified therein.

     Section 5. Filling of Vacancies: Any vacancy among the directors, occurring
from any cause whatsoever, may be filled by a majority of the remaining
directors, though less than a quorum, provided however, that the stockholders
removing any director may at the same meeting fill the vacancy caused by such
removal, and provided further, that if the directors fail to fill any such
vacancy, the stockholders may at any special meeting called for that purpose
fill such vacancy. In case of any increase in the number of directors, the
additional directors may be elected by the directors in office before such
increase.

Any person elected to fill a vacancy shall hold office, subject to the right of
removal as hereinbefore provided, until the expiration of the term of the class
for which such director was elected and until his successor is elected and
qualifies.

     Section 6. Regular Meetings: The Board of Directors shall hold an annual
meeting for the purpose of organization and the transaction of any business
immediately after the annual meeting of the stockholders, provided a quorum of
directors is present. Other regular meetings may be held at such times as may be
determined from time to time by resolution of the Board of Directors.

     Section 7. Special Meetings: Special meetings of the Board of Directors may
be called by the Chairman of the Board of Directors or by the President.

     Section 8. Notice and Place of Meetings: Meetings of the Board of Directors
may be held at the principal office of the Corporation, or at such other place
as shall be stated in the notice of such meeting. Notice of any special meeting,
and, except as the Board of Directors may otherwise determine by resolution,
notice of any regular meeting also, shall be mailed to each director addressed
to him at his residence or usual place of business at least two days before the
day on which the meeting is to be held, or if sent to him at such place by
telegraph or cable, or delivered personally or by telephone, not later than the
day before the day on which the meeting is to be held. No notice of the annual
meeting of the Board of Directors shall be required if it is held immediately
after the annual meeting of the stockholders and if a quorum is present.

     Section 9. Business Transacted at Meetings, etc.: Any business may be
transacted and any corporate action may be taken



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at any regular or special meeting of the Board of Directors at which a quorum
shall be present, whether such business or proposed action be stated in the
notice of such meeting or not, unless special notice of such business or
proposed action shall be required by statute.

     Section 10. Quorum: A majority of the Board of Directors at any time in
office shall constitute a quorum. At any meeting at which a quorum is present,
the vote of a majority of the members present shall be the act of the Board of
Directors unless the act of a greater number is specifically required by law or
by the Certificate of Incorporation or these By-laws. The members of the Board
shall act only as the Board and the individual members thereof shall not have
any powers as such.

     Section 11. Compensation: The directors shall not receive any stated salary
for their services as directors, but by resolution of the Board of Directors a
fixed fee and expenses of attendance may be allowed for attendance at each
meeting. Nothing herein contained shall preclude any director from serving the
Corporation in any other capacity, as an officer, agent or otherwise, and
receiving compensation therefor.

     Section 12. Action Without a Meeting: Any action required or permitted to
be taken at any meeting of the Board of Directors, or of any committee thereof,
may be taken without a meeting if all members of the Board or committee, as the
case may be, consent thereto in writing, and the writing or writings are filed
with the minutes of the proceedings of the Board or committee.

     Section 13. Meetings Through Use of Communications Equipment: Members of
the Board of Directors, or any committee designated by the Board of Directors,
shall, except as otherwise provided by law, the Certificate of Incorporation or
these By-laws, have the power to participate in a meeting of the Board of
Directors, or any committee, by means of a conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other, and such participation shall constitute presence in
person at the meeting.

                                   ARTICLE IV
                                   COMMITTEES.

     Section 1. Executive Committee: The Board of Directors may, by resolution
passed by a majority of the whole Board, designate two or more of their number
to constitute an Executive



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Committee to hold office at the pleasure of the Board, which Committee shall,
during the intervals between meetings of the Board of Directors, have and
exercise all of the powers of the Board of Directors in the management of the
business and affairs of the Corporation, subject only to such restrictions or
limitations as the Board of Directors may from time to time specify, or as
limited by the Delaware Corporation Law, and shall have power to authorize the
seal of the Corporation to be affixed to all papers which may require it.

Any member of the Executive Committee may be removed at any time, with or
without cause, by a resolution of a majority of the whole Board of Directors.

Any person ceasing to be a director shall ipso facto cease to be a member of the
Executive Committee.

Any vacancy in the Executive Committee occurring from any cause whatsoever may
be filled from among the directors by a resolution of a majority of the whole
Board of Directors.

     Section 2. Other Committees: Other committees, whose members need not be
directors, may be appointed by the Board of Directors or the Executive
Committee, which committees shall hold office for such time and have such powers
and perform such duties as may from time to time be assigned to them by the
Board of Directors or the Executive Committee.

Any member of such a committee may be removed at any time, with or without
cause, by the Board of Directors or the Executive Committee. Any vacancy in a
committee occurring from any cause whatsoever may be filled by the Board of
Directors or the Executive Committee.

     Section 3. Resignation: Any member of a committee may resign at any time.
Such resignation shall be made in writing and shall take effect at the time
specified therein, or, if no time be specified, at the time of its receipt by
the President or Secretary. The acceptance of a resignation shall not be
necessary to make it effective unless so specified therein.

     Section 4. Quorum: A majority of the members of a committee shall
constitute a quorum. The act of a majority of the members of a committee present
at any meeting at which a quorum is present shall be the act of such committee.
The members of a committee shall act only as a committee, and the individual
members thereof shall not have any powers as such.



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     Section 5. Record of Proceedings, etc.: Each committee shall keep a record
of its acts and proceedings, and shall report the same to the Board of Directors
when and as required by the Board of Directors.

     Section 6. Organization, Meetings, Notices, etc.: A committee may hold its
meetings at the principal office of the Corporation, or at any other place which
a majority of the committee may at any time agree upon. Each committee may make
such rules as it may deem expedient for the regulation and carrying on of its
meetings and proceedings. Unless otherwise ordered by the Executive Committee,
any notice of a meeting of such committee may be given by the Secretary of the
Corporation or by the chairman of the committee and shall be sufficiently given
if mailed to each member at his residence or usual place of business at least
two days before the day on which the meeting is to be held, or if sent to him at
such place by telegraph or cable, or delivered personally or by telephone not
later than 24 hours before the time at which the meeting is to be held.

     Section 7. Compensation: The members of any committee shall be entitled to
such compensation as may be allowed them by resolution of the Board of
Directors.

                                    ARTICLE V
                                    OFFICERS.

     Section 1. Number: The officers of the Corporation shall be a President,
one or more Vice-Presidents, a Secretary, one or more Assistant Secretaries, a
Treasurer, and one or more Assistant Treasurers, and such other officers as may
be appointed in accordance with the provisions of Section 3 of this Article V.
The Board of Directors in its discretion may also elect a Chairman of the Board
of Directors.

     Section 2. Election, Term of Office and Qualifications: The officers,
except as provided in Section 3 of this Article V, shall be chosen annually by
the Board of Directors. Each such officer shall, except as herein otherwise
provided, hold office until his successor shall have been chosen and shall
qualify. The Chairman of the Board of Directors, if any, and the President shall
be directors of the Corporation, and should any one of them cease to be a
director, he shall ipso facto cease to be such officer. Except as otherwise
provided by law, any number of offices may be held by the same person.

     Section 3. Other Officers: Other officers, including one or more additional
vice-presidents, assistant secretaries or



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assistant treasurers, may from time to time be appointed by the Board of
Directors, which other officers shall have such powers and perform such duties
as may be assigned to them by the Board of Directors or the officer or committee
appointing them.

     Section 4. Removal of Officers: Any officer of the Corporation may be
removed from office, with or without cause, by a vote of a majority of the Board
of Directors.

     Section 5. Resignation: Any officer of the Corporation may resign at any
time. Such resignation shall be in writing and shall take effect at the time
specified therein, and if no time be specified, at the time of its receipt by
the President or Secretary. The acceptance of a resignation shall not be
necessary in order to make it effective, unless so specified therein.

     Section 6. Filling of Vacancies: A vacancy in any office shall be filled by
the Board of Directors or by the authority appointing the predecessor in such
office.

     Section 7. Compensation: The compensation of the officers shall be fixed by
the Board of Directors, or by any committee upon whom power in that regard may
be conferred by the Board of Directors.

     Section 8. Chairman of the Board of Directors: The Chairman of the Board of
Directors shall be a director and shall preside at all meetings of the Board of
Directors at which he shall be present, and shall have such power and perform
such duties as may from time to time be assigned to him by the Board of
Directors.

     Section 9. President: The President shall, when present, preside at all
meetings of the stockholders, and, in the absence of the Chairman of the Board
of Directors, at meetings of the Board of Directors. He shall have power to call
special meetings of the stockholders or of the Board of Directors or of the
Executive Committee at any time. He shall be the chief executive officer of the
Corporation, and shall have the general direction of the business, affairs and
property of the Corporation, and of its several officers, and shall have and
exercise all such powers and discharge such duties as usually pertain to the
office of President.

     Section 10. Vice-Presidents: The Vice-Presidents, or any of them, shall,
subject to the direction of the Board of Directors, at the request of the
President or in his absence, or



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in case of his inability to perform his duties from any cause, perform the
duties of the President, and, when so acting, shall have all the powers of, and
be subject to all restrictions upon, the President. The Vice-Presidents shall
also perform such other duties as may be assigned to them by the Board of
Directors, and the Board of Directors may determine the order of priority among
them.

     Section 11. Secretary: The Secretary shall perform such duties as are
incident to the office of Secretary, or as may from time to time be assigned to
him by the Board of Directors, or as are prescribed by these By-laws.

     Section 12. Treasurer: The Treasurer shall perform such duties and have
powers as are usually incident to the office of Treasurer or which may be
assigned to him by the Board of Directors.

                                   ARTICLE VI
                                 CAPITAL STOCK.

     Section 1. Issue of Certificates of Stock: Certificates of capital stock
shall be in such form as shall be approved by the Board of Directors. They shall
be numbered in the order of their issue and shall be signed by the Chairman of
the Board of Directors, the President or one of the Vice-Presidents, and the
Secretary or an Assistant Secretary or the Treasurer or an Assistant Treasurer,
and the seal of the Corporation or a facsimile thereof shall be impressed or
affixed or reproduced thereon, provided, however, that where such certificates
are signed by a transfer agent or an assistant transfer agent or by a transfer
clerk acting on behalf of the Corporation and a registrar, the signature of any
such Chairman of the Board of Directors, President, Vice-President, Secretary,
Assistant Secretary, Treasurer or Assistant Treasurer may be facsimile. In case
any officer or officers who shall have signed, or whose facsimile signature or
signatures shall have been used on any such certificate or certificates shall
cease to be such officer or officers of the Corporation, whether because of
death, resignation or otherwise, before such certificate or certificates shall
have been delivered by the Corporation, such certificate or certificates may
nevertheless be adopted by the Corporation and be issued and delivered as though
the person or persons who signed such certificate or certificates, or whose
facsimile signature or signatures shall have been used thereon have not ceased
to be such officer or officers of the Corporation.



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     Section 2. Registration and Transfer of Shares: The name of each person
owning a share of the capital stock of the Corporation shall be entered on the
books of the Corporation together with the number of shares held by him, the
numbers of the certificates covering such shares and the dates of issue of such
certificates. The shares of stock of the Corporation shall be transferable on
the books of the Corporation by the holders thereof in person, or by their duly
authorized attorneys or legal representatives, on surrender and cancellation of
certificates for a like number of shares, accompanied by an assignment or power
of transfer endorsed thereon or attached thereto, duly executed, and with such
proof of the authenticity of the signature as the Corporation or its agents may
reasonably require. A record shall be made of each transfer.

The Board of Directors may make other and further rules and regulations
concerning the transfer and registration of certificates for stock and may
appoint a transfer agent or registrar or both and may require all certificates
of stock to bear the signature of either or both.

     Section 3. Lost, Destroyed and Mutilated Certificates: The holder of any
stock of the Corporation shall immediately notify the Corporation of any loss,
theft, destruction or mutilation of the certificates therefor. The Corporation
may issue a new certificate of stock in the place of any certificate theretofore
issued by it alleged to have been lost, stolen or destroyed, and the Board of
Directors may, in its discretion, require the owner of the lost, stolen or
destroyed certificate, or his legal representatives, to give the Corporation a
bond, in such sum not exceeding double the value of the stock and with such
surety or sureties as they may require, to indemnify it against any claim that
may be made against it by reason of the issue of such new certificate and
against all other liability in the premises, or may remit such owner to such
remedy or remedies as he may have under the laws of the State of Delaware.

                                  ARTICLE VII
                            DIVIDENDS, SURPLUS, ETC.

     Section 1. General Discretion of Directors: The Board of Directors shall
have power to fix and vary the amount to be set aside or reserved as working
capital of the Corporation, or as reserves, or for other proper purposes of the
Corporation, and, subject to the requirements of the Certificate of
Incorporation, to determine whether any, if any, part of the surplus or net
profits of the Corporation shall be declared as



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dividends and paid to the stockholders, and to fix the date or dates for the
payment of dividends.

                                  ARTICLE VIII
                            MISCELLANEOUS PROVISIONS.

     Section 1. Fiscal Year: The fiscal year of the Corporation shall commence
on the first day of January and end on the last day of December.

     Section 2. Corporate Seal: The corporate seal shall be in such form as
approved by the Board of Directors and may be altered at their pleasure. The
corporate seal may be used by causing it or a facsimile thereof to be impressed
or affixed or reproduced or otherwise.

     Section 3. Notices: Except as otherwise expressly provided, any notice
required by these By-laws to be given shall be sufficient if given by depositing
the same in a post office or letter box in a sealed postpaid wrapper addressed
to the person entitled thereto at his address, as the same appears upon the
books of the Corporation, or by telegraphing or cabling the same to such person
at such addresses; and such notice shall be deemed to be given at the time it is
mailed, telegraphed or cabled.

     Section 4. Waiver of Notice: Any stockholder or director may at any time,
by writing or by telegraph or by cable, waive any notice required to be given
under these By-laws, and if any stockholder or director shall be present at any
meeting his presence shall constitute a waiver of such notice.

     Section 5. Checks, Drafts, etc.: All checks, drafts or other orders for the
payment of money, notes or other evidences of indebtedness issued in the name of
the Corporation, shall be signed by such officer or officers, agent or agents of
the Corporation, and in such manner, as shall from time to time be designated by
resolution of the Board of Directors.

     Section 6. Deposits: All funds of the Corporation shall be deposited from
time to time to the credit of the Corporation in such bank or banks, trust
companies or other depositories as the Board of Directors may select, and, for
the purpose of such deposit, checks, drafts, warrants and other orders for the
payment of money which are payable to the order of the Corporation, may be
endorsed for deposit, assigned and delivered by any officer of the Corporation,
or by such agents of the Corporation as the Board of Directors or the President
may authorize for that purpose.



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     Section 7. Voting Stock of Other Corporations: Except as otherwise ordered
by the Board of Directors or the Executive Committee, the President or the
Treasurer shall have full power and authority on behalf of the Corporation to
attend and to act and to vote at any meeting of the stockholders of any
corporation of which the Corporation is a stockholder and to execute a proxy to
any other person to represent the Corporation at any such meeting, and at any
such meeting the President or the Treasurer or the holder of any such proxy, as
the case may be, shall possess and may exercise any and all rights and powers
incident to ownership of such stock and which, as owner thereof, the Corporation
might have possessed and exercised if present. The Board of Directors or the
Executive Committee may from time to time confer like powers upon any other
person or persons.

     Section 8. Indemnification of Officers and Directors: The Corporation shall
indemnify any and all of its directors or officers, including former directors
or officers, and any employee, who shall serve as an officer or director of any
corporation at the request of this Corporation, to the fullest extent permitted
under and in accordance with the laws of the State of Delaware.

                                   ARTICLE IX
                                   AMENDMENTS.

     The Board of Directors shall have the power to make, rescind, alter, amend
and repeal these By-laws, provided, however, that the stockholders shall have
power to rescind, alter, amend or repeal any by-laws made by the Board of
Directors, and to enact by-laws which if so expressed shall not be rescinded,
altered, amended or repealed by the Board of Directors. No change of the time or
place for the annual meeting of the stockholders for the election of directors
shall be made except in accordance with the laws of the State of Delaware.
Notwithstanding the foregoing, Article III, Section 1, may not be altered,
amended or repealed in whole or in part, unless authorized by the affirmative
vote of the holders of not less than two thirds (2/3) of the outstanding voting
power entitled to vote, or by a majority of the entire Board of Directors then
in office.

Dated: August 10, 2000


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