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                                                                   Exhibit 10.44

                                           [As amended through January 18, 2001]

                         CSG SYSTEMS INTERNATIONAL, INC.
                  STOCK OPTION PLAN FOR NON-EMPLOYEE DIRECTORS


     1. Purpose. The purpose of the CSG Systems International, Inc. Stock Option
Plan for Non-Employee Directors (the "Plan") is to foster and promote the
long-term financial success of the Company and thereby increase stockholder
value by attracting and retaining as directors of the Company highly qualified
persons who are not employees of the Company or a Subsidiary.

     2. Certain Definitions.

     "Board" means the Board of Directors of the Company.

     "Code" means the Internal Revenue Code of 1986, as amended from time to
time, or any successor thereto. References to a particular section of the Code
shall include any regulations issued under such section.

     "Common Stock" means the Common Stock, $0.01 par value per share, of the
Company.

     "Company" means CSG Systems International, Inc., a Delaware corporation.

     "Director" means a person then serving as a member of the Board of the
Company.

     "Exchange Act" means the Securities Exchange Act of 1934, as amended from
time to time.

     "Fair Market Value" means, as determined by the Board, the last sale price
of the Common Stock as quoted on the Nasdaq National Market System on the
trading day for which the determination is being made, or, in the event that no
such sale takes place on such day, the average of the reported closing bid and
asked prices on such day, or, if the Common Stock of the Company is listed on a
national securities exchange, the last reported sale price on the principal
national securities exchange on which the Common Stock is listed or admitted to
trading on the trading day for which the determination is being made, or, if no
such reported sale takes place on such day, the average of the closing bid and
asked prices on such day on the principal national securities exchange on which
the Common Stock is listed or admitted to trading, or, if the Common Stock is
not quoted on such National Market System nor listed or admitted to trading on a
national securities exchange, the average of the closing bid and asked prices in
the over-the-counter market on the day for which the determination is being made
as reported through Nasdaq, or, if bid and asked prices for the Common Stock on
such day are not reported through Nasdaq, the average of the bid and asked
prices for such day as furnished by any New York Stock Exchange member firm
regularly making a market in the Common Stock selected for such purpose by the
Board, or, if none of the foregoing is applicable, then the fair market value of
the Common Stock as determined in good faith by the Board in its sole
discretion.
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     "Stock Option" means an option to purchase Common Stock granted pursuant to
the Plan.

     "Subsidiary" means a corporation, domestic or foreign, of which not less
than 50% of the voting shares are held by the Company or by a Subsidiary,
whether or not such corporation now exists or hereafter is organized or acquired
by the Company or by a Subsidiary.

     3. Administration. The Plan shall be administered by the Board, and the
Board shall have authority to grant Stock Options to eligible Directors from
time to time pursuant to the Plan. Subject to the applicable provisions of the
Plan, the Board shall have authority to interpret the provisions of the Plan and
to decide all questions of fact arising in the application of such provisions;
to select the Directors to whom Stock Options shall be granted; to determine
when, whether, and in what amounts Stock Options shall be granted; to determine
the amount, terms, and conditions of each Stock Option; to determine the Fair
Market Value of the Common Stock from time to time; to authorize persons to
execute on behalf of the Company any agreement required to be entered into under
the Plan; to adopt, alter, and repeal such administrative rules, guidelines, and
practices governing the Plan as the Board from time to time shall deem
advisable; and to make all other determinations necessary or advisable for the
administration of the Plan. Unless otherwise expressly provided in the Plan, all
decisions and determinations made by the Board pursuant to the provisions of the
Plan shall be made in the sole discretion of the Board and shall be final and
binding on all persons, including but not limited to the Company, the Directors
to whom Stock Options are granted, the heirs and legal representatives of such
Directors, and the personal representatives and beneficiaries of the estates of
such Directors.

     4. Common Stock Subject to the Plan. The Company shall reserve and keep
available for issuance under the Plan four hundred fifty thousand (450,000)
shares of Common Stock, subject to adjustment pursuant to Section 17. Such
shares may consist in whole or in part of authorized and unissued shares or
treasury shares or any combination thereof. Except as otherwise provided in the
Plan, any shares subject to a Stock Option which expires or terminates
unexercised as to such shares shall again be available for the grant of Stock
Options.

     5. Eligibility to Receive Stock Options. Stock Options may be granted under
the Plan only to Directors who are not employees of the Company or a Subsidiary
on the date of the grant.

     6. Stock Options. All Stock Options shall be nonqualified stock options for
purposes of the Code. Stock Options shall be evidenced by agreements in such
form as the Board shall approve from time to time; such agreements shall contain
in substance the following terms and conditions and may contain such additional
terms and conditions, not inconsistent with the terms of the Plan, as the Board
shall deem appropriate:

          (a) Type of Option. Each option agreement shall identify the Stock
     Option evidenced thereby as a nonqualified stock option for purposes of the
     Code.

          (b) Option Price. Each option agreement shall set forth the number of
     shares of Common Stock covered by the stock option and the applicable
     option exercise price per

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     share, which price shall not be less than the Fair Market Value of the
     Common Stock on the date the Stock Option is granted or less than the par
     value of the Common Stock.

          (c) Term. Each option agreement shall state the period or periods of
     time during which the Stock Option may be exercised, in whole or in part,
     which shall be such period or periods of time as the Board may determine at
     the time the Stock Option is granted; provided, that no Stock Option shall
     be exercisable more than ten years after the date of its grant; and
     provided further, that each Stock Option shall become and remain
     exercisable as provided in the option agreement relating to such Stock
     Option.

          (d) Payment for Shares. Each option agreement shall require the option
     exercise price per share to be paid in full in cash at the time the Stock
     Option is exercised with respect to any of the shares covered by such Stock
     Option.

     7. Cessation of Service as a Director. Unless the applicable option
agreement provides otherwise, if the grantee of a Stock Option ceases to be a
Director for any reason other than retirement from the Board under the
circumstances described in Section 8 or death, then each outstanding but
unexercised Stock Option held by such grantee shall continue to be exercisable
only to the extent that it was exercisable at the time that such grantee ceased
to be a Director and only until the earlier of (i) ninety days after such
grantee ceased to be a Director or (ii) the expiration of the term of such Stock
Option; and to the extent not exercisable or not exercised (if exercisable) by
such applicable date, such Stock Option shall terminate and be of no further
force or effect.

     8. Retirement from Board. Unless the applicable option agreement provides
otherwise, if the grantee of a Stock Option ceases to be a Director (other than
by reason of death) and at the time of such occurrence (the "Retirement Date")
is at least age 65 with ten or more years of service as a Director or is at
least age 70 with five or more years of service as a Director, then each
outstanding but unexercised Stock Option held by such grantee on the Retirement
Date shall continue to be or become exercisable in accordance with its terms
until the earlier of (i) five years after the Retirement Date or (ii) the
expiration of the term of such Stock Option; and to the extent not exercisable
or not exercised (if exercisable) by such applicable date, such Stock Option
shall terminate and be of no further force or effect.

     9. Death. Unless the applicable option agreement provides otherwise, if the
grantee of a Stock Option dies, then each outstanding but unexercised Stock
Option which had been held by such grantee for at least twelve months as of the
date of such grantee's death automatically shall become exercisable in full (if
not already exercisable) upon such grantee's death. Each outstanding but
unexercised Stock Option which becomes exercisable pursuant to the preceding
sentence and each outstanding but unexercised Stock Option held by such grantee
which was exercisable on the date of such grantee's death may be exercised by
the legal representative of such grantee's estate or by the beneficiaries of
such estate to whom such Stock Option is distributed until the earlier of (i)
three years after the date of such grantee's death or (ii) the expiration of the
term of such Stock Option; and to the extent not exercisable or not exercised
(if exercisable) by such applicable date, such Stock Option shall terminate and
be of no further force or effect.

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     10. Acceleration of Exercisability. The Board shall have the authority to
accelerate the exercisability of any outstanding Stock Option, subject to any
applicable requirements of the Plan, under such circumstances and upon such
terms and conditions as the Board shall deem appropriate.

     11. General Restrictions. Each Stock Option grant under the Plan shall be
subject to the requirement that if at any time the Board shall determine that
(i) the listing, registration, or qualification of the shares of Common Stock
subject or related thereto upon any securities market or securities exchange or
under any state or federal law, (ii) the consent or approval of any governmental
regulatory body, or (iii) an agreement by the grantee of such Stock Option with
respect to the disposition of the shares of Common Stock subject thereto is
necessary or desirable as a condition of, or in connection with, such grant or
the issuance of shares of Common Stock thereunder, then such Stock Option grant
may not be consummated and any rights under such Stock Option may not be
exercised in whole or in part unless and until such listing, registration,
qualification, consent, approval, or agreement shall have been effected or
obtained upon conditions acceptable to the Board.

     12. Rights of a Stockholder. The grantee of a Stock Option shall have no
rights as a stockholder of the Company with respect to the shares of Common
Stock subject to such Stock Option unless and until certificates for such shares
of Common Stock are issued to such grantee upon the timely and proper exercise
of such Stock Option.

     13. No Right to Continue as a Director. Nothing in the Plan or in any
agreement entered into pursuant to the Plan shall confer upon any Director the
right to continue to serve as a Director of the Company.

     14. Indemnification. No member of the Board, and no officer or employee of
the Company acting on behalf of the Board, shall be personally liable for any
action, determination, or interpretation taken or made in good faith with
respect to the Plan; and all members of the Board and each officer or employee
of the Company acting on behalf of the Board shall, to the extent permitted by
law, be fully indemnified by the Company in respect of any such action,
determination, or interpretation.

     15. Non-Assignability. No Stock Option granted under the Plan shall be
assignable or transferable by the grantee thereof except by will, by the laws of
descent and distribution, or by such other means (if any) or in such other
manner (if any) as the Board may approve from time to time. No right or benefit
under the Plan or any Stock Option granted under the Plan shall be liable for
the debts, liabilities, or alimony obligations of the person entitled to such
right or benefit, either by assignment, attachment, or any other method, and
shall not be subject to be taken by the creditors of the person entitled to such
right or benefit by any process whatsoever.

     16. Nonuniform Determinations. The Board's determinations under the Plan
(including but not limited to determinations of the persons to receive Stock
Option grants, the amount and timing of such grants, and the terms and
provisions of such grants) need not be uniform and may be

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made by the Board selectively among the Directors who receive, or are eligible
to receive, Stock Option grants.

     17. Adjustments. In the event of any change in the outstanding shares of
Common Stock by reason of a stock dividend or distribution, stock split,
recapitalization, merger, reorganization, consolidation, split-up, spin-off,
combination of shares, exchange of shares, or other change in corporate
structure affecting the Common Stock, the Board shall make appropriate
adjustments in (a) the aggregate number of shares of Common Stock (i) reserved
for issuance under the Plan and (ii) covered by outstanding Stock Option grants
and (b) the exercise price related to outstanding Stock Options; provided, that
the number of shares subject to any Stock Option always shall be a whole number.

     18. Termination and Amendment. The Board may terminate the Plan or amend
the Plan or any portion thereof at any time, including but not limited to
amendments to the Plan necessary to comply with the requirements of Section
16(b) of the Exchange Act or applicable regulations thereunder, except that the
Board may not increase the maximum number of shares which may be issued under
the Plan (other than by way of adjustments made pursuant to Section 17), extend
the maximum period during which any Stock Option may be exercised, extend the
term of the Plan, decrease the minimum option price to less than the Fair Market
Value on the date of the grant of a Stock Option, or change the category of
persons eligible to participate in the Plan without stockholder approval if such
approval is required by the applicable rules of the Securities and Exchange
Commission, the Nasdaq National Market, or any national securities exchange on
which the Common Stock is listed. The termination or any amendment of the Plan
shall not, without the consent of a Stock Option grantee, adversely affect such
grantee's rights under a Stock Option previously granted to such grantee. The
Board may amend the terms and conditions of any Stock Option grant previously
made, prospectively or retroactively, as long as such amendment is not
inconsistent with the terms of the Plan; but, except as otherwise expressly
permitted by the Plan and subject to Section 17, no such amendment shall
adversely affect the rights of the grantee of such Stock Option without such
grantee's consent.

     19. Term of Plan. Subject to approval of the Plan by the stockholders of
the Company not later than December 31, 1997, the Plan shall become effective on
the date on which the Plan is approved and adopted by the Board and shall
terminate for purposes of further Stock Option grants on the first to occur of
(i) December 31, 2006, or (ii) the effective date of the termination of the Plan
by the Board pursuant to Section 18. No Stock Options may be granted under the
Plan after the termination of the Plan, but such termination shall not affect
any Stock Options outstanding at the time of such termination or the authority
of the Board to continue to administer the Plan apart from the making of further
Stock Option grants. The Board may grant Stock Options under the Plan prior to
approval of the Plan by the stockholders of the Company, but any Stock Options
so granted shall be subject in all respects to such approval. Notwithstanding
the provisions of any option agreement evidencing a Stock Option granted prior
to approval of the Plan by the stockholders of the Company, such Stock Option
may not be exercised to any extent prior to such stockholder approval. If such
stockholder approval is not given by December 31, 1997, then the Plan and all
Stock Options granted thereunder automatically shall terminate and be of no
further force or effect at the close of business on December 31, 1997.

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     20. Governing Law. The Plan shall be governed by and construed in
accordance with the laws of Delaware.

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