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                                                                     EXHIBIT 3.1


                   AMENDMENT TO AMENDED AND RESTATED BY-LAWS
                   -----------------------------------------
                              OF ALLSCRIPTS, INC.
                              -------------------
                          (effective April 7, 2000)

     The fourth sentence of Article II, Section 1 (Annual Meeting) is hereby
amended to read in its entirety as follows:

          For business to be properly brought before an annual meeting by a
     stockholder, the stockholder must have given timely notice thereof in
     writing to the secretary of the Corporation not less than one hundred and
     twenty (120) days prior to the anniversary date of the immediately
     preceding annual meeting nor more than one hundred and fifty (150) days
     prior to the anniversary date of the immediately preceding annual meeting.

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                                    BY-LAWS

                                      OF

                               ALLSCRIPTS, INC.
                           (A Delaware Corporation)


                                  ARTICLE I.

                                    Offices

     Section 1.  The registered office of Allscripts, Inc. (the "Corporation")
shall be in Wilmington, New Castle County, Delaware.

     Section 2.  The Corporation shall have its principal office at 2401
Commerce Drive, Libertyville, Illinois, and it may also have offices at such
other places as the board of directors may from time to time determine.


                                  ARTICLE II.

                                 Stockholders

     Section 1.  Annual Meeting. The annual meeting of stockholders for the
                 --------------
election of directors and for the transaction of such other business as may
properly come before the meeting shall be held on such date as the board of
directors shall fix each year. At an annual meeting of stockholders, only such
business shall be conducted as shall have been properly brought before the
meeting. To be properly brought before an annual meeting, business must be (a)
specified in the notice of meeting, or any supplement thereto, given by or at
the direction of the board of directors, (b) otherwise properly brought before
the meeting by or at the direction of the board of directors, or (c) otherwise
properly brought before the meeting by a stockholder. For business to be
properly brought before an annual meeting by a stockholder, the stockholder must
have given timely notice thereof in writing to the secretary of the Corporation
not less than one hundred and twenty (120) days prior to the meeting nor more
than one hundred and fifty (150) days prior to the meeting. A stockholder's
notice to the secretary of the Corporation shall set forth as to each matter the
stockholder proposes to bring before the annual meeting (a) a brief description
of the business desired to be brought before the annual meeting, (b) the name
and address, as they appear on the Corporation's stockholder records, of the
stockholder proposing such business, (c) the class and number of shares of the
Corporation which are beneficially owned by the stockholder, and (d) any
material interest of the stockholder in such business.  Irrespective of anything
in these by-laws to the contrary, no business shall be conducted at an annual
meeting except in accordance with the procedures set forth in this Section 1.
The presiding officer of an annual meeting shall, if the facts warrant,
determine and declare to the meeting that business was not properly brought
before the meeting in accordance with the provisions of this Section 1, and if
it is so determined, shall so declare to the meeting and any such business not
properly brought before the meeting shall not be transacted.

     Section 2.  Special Meetings. Special meetings of the stockholders may be
                 ----------------
called only by the chairman, the president or the board of directors pursuant to
a resolution approved by a majority of the entire board of directors.

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     Section 3.  Stockholder Action; How Taken. Any action required or permitted
                 ------------------
to be taken by the stockholders of the Corporation must be effected at a duly
called annual or special meeting of such holders and may not be effected by any
consent in writing by such holders.

     Section 4.  Place of Meeting. The board of directors may designate any
                 ----------------
place, either within or without Delaware, as the place of meeting for any annual
or special meeting. In the absence of any such designation, the place of meeting
shall be the principal office of the Corporation designated in Section 2 of
Article I of these by-laws.

     Section 5.  Notice of Meetings. Written or printed notice stating the
                 ------------------
place, day and hour of the meeting and, in case of a special meeting, the
purpose or purposes for which the meeting is called, shall be delivered not less
than ten nor more than sixty days before the date of the meeting, or in the case
of a merger or consolidation, not less than twenty nor more than fifty days
before the date of the meeting, either personally or by mail, by or at the
direction of the chairman or the president, or the secretary, or the officer or
persons calling the meeting, to each stockholder of record entitled to vote at
such meeting. If mailed, such notice shall be deemed to be delivered when
deposited in the United States mails in a sealed envelope addressed to the
stockholder at his address as it appears on the records of the Corporation with
postage thereon prepaid.

     Section 6.  Record Date. For the purpose of determining (a) stockholders
                 -----------
entitled to notice of or to vote at any meeting of stockholders, or (b)
stockholders entitled to receive payment of any dividend, or (c) stockholders
for any other purpose, the board of directors may fix in advance a date as the
record date for any such determination of stockholders, such date in any case to
be not more than sixty days and not less than ten days, or in the case of a
merger or consolidation not less than twenty days, prior to the date on which
the particular action requiring such determination of stockholders is to be
taken.

     Section 7.  Quorum. The holders of not less than one-third of the stock
                 ------
issued and outstanding and entitled to vote thereat, present in person or
represented by proxy, shall be requisite and shall constitute a quorum at all
meetings of the stockholders for the transaction of business except as otherwise
provided by statute, by the certificate of incorporation or by these by-laws.
If, however, such quorum shall not be present or represented at any meeting of
the stockholders, the chairman of the meeting shall have the power to adjourn
the meeting from time to time, without notice other than announcement at the
meeting, until a quorum shall be present or represented. At such adjourned
meeting at which a quorum shall be present or represented, any business may be
transacted which might have been transacted at the meeting as originally
notified.

     When a quorum is present at any meeting, the vote of the holders of a
majority of the stock having voting power present in person or represented by
proxy shall decide any question brought before such meeting, unless the question
is one upon which by express provision of the statutes or of the certificate of
incorporation or of these by-laws, a different vote is required in which case
such express provision shall govern and control the decision of such question.


     Section 8.  Qualification of Voters. The board of directors may fix a day
                 -----------------------
and hour not more than sixty nor less than ten days prior to the day of holding
any meeting of stockholders as the time as of which the stockholders entitled to
notice of and to vote at such a meeting shall be determined. Only those persons
who were holders of record of voting stock at such time shall be entitled to
notice of and to vote at such meeting.

     Section 9.  Procedure. The order of business and all other matters of
                 ---------
procedure at every meeting of stockholders shall be determined by the chairman
of the meeting.  The board of directors shall

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appoint two or more inspectors of election to serve at every meeting of
stockholders at which directors are to be elected.


                                 ARTICLE III.

                                   Directors

      Section 1.  Number, Election and Terms. Except as otherwise fixed pursuant
                  --------------------------
to the provisions of Article Fourth of the certificate of incorporation relating
to the rights of the holders of any class or series of stock having a preference
over the common stock as to dividends or upon liquidation to elect additional
directors under specified circumstances, the number of directors shall be a
minimum of three and fixed from time to time by the board of directors. The
directors, other than those who may be elected by the holders of any class or
series of stock having a preference over the common stock as to dividends or
upon liquidation, shall be classified, with respect to the time for which they
severally hold office, into three classes, as near equal in number as possible,
as determined by the board of directors, one class to hold office initially for
a term expiring at the annual meeting of stockholders to be held in 2000,
another class to hold office initially for a term expiring at the annual meeting
of stockholders to be held in 2001 and another class to hold office initially
for a term expiring at the annual meeting of stockholders to be held in 2002,
with the members of each class to hold office until their successors are elected
and qualified. At each annual meeting of stockholders, the successors of the
class of directors whose term expires at that meeting shall be elected to hold
office for a term expiring at the annual meeting of stockholders held in the
third year following the year of their election.

     The term the "entire board" as used in these by-laws means the total number
of directors which the Corporation would have if there were no vacancies.

     Subject to the rights of holders of any class or series of stock having a
preference over the common stock as to dividends or upon liquidation,
nominations for the election of directors may be made by the board of directors
or a committee appointed by the board of directors or by any stockholder
entitled to vote in the election of directors generally. However, any
stockholder entitled to vote in the election of directors generally may nominate
one or more persons for election as directors at a meeting only if written
notice of such stockholder's intent to make such nomination or nominations has
been given, either by personal delivery or by United States mail, postage
prepaid, to the secretary of the Corporation not later than (a) with respect to
an election to be held at an annual meeting of stockholders, one hundred twenty
(120) days nor earlier than one hundred fifty (150) days prior to the
anniversary date of the immediately preceding annual meeting, and (b) with
respect to an election to be held at a special meeting of stockholders for the
election of directors, the close of business on the tenth day following the date
on which notice of such meeting is first given to stockholders. Each such notice
shall set forth: (a) the name and address of the stockholder who intends to make
the nomination and of the person or persons to be nominated; (b) a
representation that the stockholder is a holder of record of stock of the
Corporation entitled to vote at such meeting and intends to appear in person or
by proxy at the meeting to nominate the person or persons specified in the
notice; (c) a description of all arrangements or understandings between the
stockholder and each nominee and any other person or persons, naming such person
or persons, pursuant to which the nomination or nominations are to be made by
the stockholder; (d) such other information regarding each nominee proposed by
such stockholder as would be required to be included in a proxy statement filed
pursuant to the proxy rules of the Securities and Exchange Commission; and (e)
the consent of each nominee to serve as a director of the Corporation if so
elected. The chairman of the meeting may refuse to acknowledge the nomination of
any person not made in compliance with the foregoing procedure.

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     Section 2.  Newly Created Directorships and Vacancies. Except as otherwise
                 -----------------------------------------
fixed pursuant to the provisions of Article Fourth of the certificate of
incorporation relating to the rights of the holders of any class or series of
stock having a preference over the common stock as to dividends or upon
liquidation to elect directors under specified circumstances, newly created
directorships resulting from any increase in the number of directors and any
vacancies on the board of directors resulting from death, resignation,
disqualification, removal or other cause shall be filled solely by the
affirmative vote of a majority of the remaining directors then in office, even
though less than a quorum of the board of directors. Any director elected in
accordance with the preceding sentence shall hold office for the remainder of
the full term of the class of directors to which such director's predecessor
shall have been elected and qualified. No decrease in the number of directors
constituting the board of directors shall shorten the term of any incumbent
director.

     Section 3.  Removal. Subject to the rights of any class or series of stock
                 -------
having a preference over the common stock as to dividends or upon liquidation to
elect directors under specified circumstances, any director may be removed from
office only for cause and only by the affirmative vote of the holders of 80% of
the combined voting power of the then outstanding shares of stock entitled to
vote generally in the election of directors, voting together as a single class.

     Section 4.  Regular Meetings. Regular meetings of the board of directors
                 ----------------
shall be held at such times and place as the board of directors may from time to
time determine.

     Section 5.  Special Meetings. Special meetings of the board of directors
                 ----------------
may be called by or at the request of the chairman or the president or by an
officer of the Corporation upon the request of a majority of the entire board.
The person or persons authorized to call special meetings of the board of
directors may fix any place, either within or without Delaware, as the place for
holding any special meeting of the board of directors called by them.

     Section 6.  Notice. Notice of regular meetings of the board of directors
                 ------
need not be given. Notice of every special meeting of the board of directors
shall be given to each director at his usual place of business, or at such other
address as shall have been furnished by him for the purpose. Such notice shall
be given at least twenty-four hours before the meeting by telephone, by personal
delivery, by commercial courier, by mail or by facsimile transmission. Such
notice need not include a statement of the business to be transacted at, or the
purpose of, any such meeting.

     Section 7.  Quorum. A majority of the entire Board shall constitute a
                 ------
quorum for the transaction of business at any meeting of the board of directors,
provided, that if less than a majority of the entire board is present at said
meeting, a majority of the directors present may adjourn the meeting from time
to time until a quorum is obtained without further notice. The act of the
majority of the directors present at a meeting at which a quorum is present
shall be the act of the board of directors unless the act of a greater number is
required by the certificate of incorporation or the by-laws of the Corporation.

     Section 8.  Compensation. Directors who are also full time employees of the
                 ------------
Corporation shall not receive any compensation for their services as directors
but they may be reimbursed for reasonable expenses of attendance. By resolution
of the board of directors, all other directors may receive either an annual fee
or a fee for each meeting attended, or both, and expenses of attendance, if any,
at each regular or special meeting of the board of directors or of a committee
of the board of directors; provided, that nothing herein contained shall be
construed to preclude any director from serving the Corporation in any other
capacity and receiving compensation therefor.

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     Section 9.   Committees. The board of directors may, by resolution passed
                  -----------
by a majority of the entire board, designate one or more committees, each
committee to consist of two or more of the directors of the Corporation, which,
to the extent provided in the resolution, shall have and may exercise the powers
of the board of directors in the management of the business and affairs of the
Corporation and may authorize the seal of the Corporation to be affixed to all
papers which may require it. Such committee or committees shall have such name
or names as may be determined from time to time by resolution adopted by the
board of directors. Each committee shall keep regular minutes of its meetings
and report the same to the board of directors when required.

     Section 10.  Director Emeritus. The Board of Directors may by resolution
                  -----------------
appoint any former director who has retired from the Board of Directors as a
Director Emeritus. Directors Emeritus may, but are not required to, attend all
meetings (regular and special) of the Board of Directors and will receive notice
of such meetings; however, they shall not have the right to vote and they shall
be excluded from the number of directors for quorum and other purposes.
Directors Emeritus shall be appointed for one year terms and may be reappointed
for up to two additional one year terms.


                                  ARTICLE IV.

                                   Officers

     Section 1.  Number. The officers of the Corporation shall be a chairman, a
                 ------
vice-chairman (if elected by the board of directors), a president, an executive
vice president (if elected by the board of directors), one or more vice
presidents (the number thereof to be determined by the board of directors), a
treasurer, a secretary and such other officers as may be elected in accordance
with the provisions of this Article.

     Section 2.  Election and Term of Office. The officers of the Corporation
                 ---------------------------
shall be elected annually by the board of directors at the first meeting of the
board of directors held after each annual meeting of stockholders. If the
election of officers shall not be held at such meeting, such election shall be
held as soon thereafter as convenient. Vacancies may be filled or new offices
created and filled at any meeting of the board of directors. Each officer shall
hold office until his successor shall have been duly elected and shall have
qualified or until his death or until he shall resign or shall have been removed
in the manner hereinafter provided.

     Section 3.  Removal. Any officer or agent elected or appointed by the board
                 -------
of directors may be removed by the board of directors whenever in its judgment
the best interests of the Corporation would be served thereby, but such removal
shall be without prejudice to the contract rights, if any, of the person so
removed.

     Section 4.  Vacancies. A vacancy in any office because of death,
                 ---------
resignation, removal, disqualification or otherwise, may be filled by the board
of directors for the unexpired portion of the term.

     Section 5.  Chairman. The chairman shall preside at all meetings of the
                 --------
stockholders and the board of directors. If so appointed by the board of
directors he shall be the chief executive officer of the Corporation and shall
have those duties and responsibilities described in Section 8 of this Article.
He shall perform such other duties as may be prescribed by the board of
directors.

     Section 6.  Vice-Chairman. The vice-chairman (if elected by the board of
                 -------------
directors) shall, in the absence of the chairman, preside at all meetings of the
stockholders and the board of directors. If so appointed by the board of
directors he shall be the chief executive officer and shall have those duties
and

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responsibilities described in Section 8 of this Article. He shall perform such
other duties as may be prescribed by the board of directors and by the chief
executive officer if he does not have that position.

     Section 7.   President. The president shall in general be in charge of all
                  ---------
operations of the Corporation and shall direct and administer the activities of
the Corporation in accordance with the policies, goals and objectives
established by the chief executive officer and the board of directors. In the
absence of the chief executive officer, the president shall assume his duties
and responsibilities. In the absence of the chairman and vice-chairman he shall
preside at all meetings of the stockholders and board of directors. He shall
perform such other duties as may be prescribed by the board of directors and
chief executive officer if he does not have that position.

     Section 8.   Chief Executive Officer. The chief executive officer of the
                  -----------------------
Corporation shall be either the chairman, the vice-chairman or the president as
determined by the board of directors. The chief executive officer shall provide
overall direction and administration of the business of the Corporation, he
shall interpret and apply the policies of the board of directors, establish
basic policies within which the various corporate activities are carried out,
guide and develop long range planning and evaluate activities in terms of
objectives. He may sign (with the secretary or any other proper officer of the
Corporation thereunto authorized by the board of directors, if such additional
signature is necessary under the terms of the instrument document being executed
or under applicable law, stock certificates of the Corporation, any deeds,
mortgages, bonds, contracts, or other instruments except in cases where the
signing and execution thereof shall be required by law to be otherwise signed or
executed, and he may execute proxies on behalf of the Corporation with respect
to the voting of any shares of stock owned by the Corporation. He shall have the
power to (1) designate management committees of employees deemed essential in
the operations of the Corporation, its divisions or subsidiaries, and appoint
members thereof, subject to the approval of the board of directors; (2) appoint
certain employees of the Corporation as vice presidents of one or several
divisions or operations of the Corporation, subject to the approval of the board
of directors, provided however, that any vice president so appointed shall not
be an officer of the Corporation for any other purpose; and (3) appoint such
other agents and employees as in his judgment may be necessary or proper for the
transaction of the business of the Corporation and in general shall perform all
duties incident to the office of chief executive.

     Section 9.   Executive Vice President. The executive vice president (if
                  ------------------------
elected by the board of directors) shall report to either the chief executive
officer or the president as determined in the corporate organization plan
established by the board of directors. He shall direct and coordinate such major
activities as shall be delegated to him by his superior officer in accordance
with policies established and instructions issued by his superior officer, the
chief executive officer, or the board of directors.

     Section 10.  Vice President. The board of directors may elect one or
                  --------------
several vice presidents. Each vice president shall report to either the chief
executive officer, the chief operating officer or the executive vice president
as determined in the corporate organization plan established by the board of
directors. Each vice president shall perform such duties as may be delegated to
him by his superior officers and in accordance with the policies established and
instructions issued by his superior officer, the chief executive officer or the
board of directors. The board of directors may designate any vice president as a
senior vice president and a senior vice president shall be senior to all other
vice presidents and junior to the executive vice president. In the event there
is more than one senior vice president, then seniority shall be determined by
and be the same as the annual order in which their names are presented to and
acted on by the board of directors.

     Section 11.  The Treasurer. The treasurer shall (a) have charge and custody
                  -------------
of and be responsible for all funds and securities of the Corporation; receive
and give receipts for moneys due and payable to the Corporation from any source
whatsoever, and deposit all such moneys in the name of the

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Corporation in such banks, trust companies or other depositories as shall be
selected by the Corporation; (b) in general perform all the duties incident to
the office of treasurer and such other duties as from time to time may be
assigned to him by the chief executive officer, chief operating officer or by
the board of directors. If required by the board of directors, the treasurer
shall give a bond for the faithful discharge of his duties in such sum and with
such surety or sureties as the board of directors shall determine.

     Section 12.  The Assistant Treasurer. The assistant treasurer (or, if more
                  -----------------------
than one, the assistant treasurers) shall, in the absence or disability of the
treasurer, perform the duties and exercise the powers of the treasurer and shall
perform such other duties and have such other powers as the board of directors
may from time to time prescribe.

     Section 13.  The Secretary. The secretary shall: (a) keep the minutes of
                  -------------
the stockholders' and the board of directors' meetings in one or more books
provided for that purpose; (b) see that all notices are duly given in accordance
with the provisions of these by-laws or as required by law; (c) be custodian of
the corporate records and of the seal of the Corporation and see that the seal
of the corporation is affixed to all stock certificates prior to the issue
thereof and to all documents, the execution of which on behalf of the
Corporation under its seal is duly authorized in accordance with the provisions
of these by-laws or as required by law; (d) be custodian of the corporate
records and of the seal of the Corporation and see that the seal of the
Corporation is affixed to all stock certificates prior to the issue thereof and
to all documents, the execution of which on behalf of the Corporation under its
seal is duly authorized in accordance with the provisions of these by-laws; (e)
keep a register of the post office address of each stockholder which shall be
furnished to the secretary by such stockholder; (f) sign with the chairman,
president, or a vice president, stock certificates of the Corporation, the issue
of which shall have been authorized by resolution of the board of directors; (g)
have general charge of the stock transfer books of the Corporation; (h) in
general perform all duties incident to the office of secretary and such other
duties as from time to time may be assigned to him by the chief executive
officer, chief operating officer or by the board of directors.

     Section 14.  The Assistant Secretary. The assistant secretary (or, if more
                  -----------------------
than one, the assistant secretaries) shall in the absence or disability of the
secretary, perform the duties and exercise the powers of the secretary and shall
perform such other duties and have such other powers as the board of directors
may from time to time prescribe.


                                  ARTICLE V.

                                  Fiscal Year

     The fiscal year of the Corporation shall begin on the first day of January
in each year and end on the thirty-first day of December in each year.


                                  ARTICLE VI.

                                     Seal

     The board of directors shall provide a corporate seal which shall be in the
form of a circle and shall have inscribed thereon the name of the Corporation
and the words "Corporate Seal, Delaware".

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                                 ARTICLE VII.

                               Waiver of Notice

     Whenever any notice whatsoever is required to be given under the provisions
of these by-laws or under the provisions of the certificate of incorporation or
under the provisions of the laws of the state of Delaware, waiver thereof in
writing, signed by the person or persons entitled to such notice, whether before
or after the time stated therein, shall be deemed equivalent to the giving of
such notice.


                                 ARTICLE VIII.

                                  Amendments

     Subject to the provisions of the certificate of incorporation, these by-
laws may be altered, amended or repealed at any regular meeting of the
stockholders, or at any special meeting of stockholders duly called for that
purpose, by a majority vote of the shares represented and entitled to vote at
such meeting; provided that in the notice of such special meeting notice of such
purpose shall be given. Subject to the laws of the State of Delaware, the
certificate of incorporation and these by-laws, the board of directors may by a
majority vote of those present at any meeting at which a quorum is present amend
these by-laws, or enact such other by-laws as in their judgment may be advisable
for the regulation of the conduct of the affairs of the Corporation.

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