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             EXHIBIT 4.5 - AMENDMENT TO INVESTORS' RIGHTS AGREEMENT

                                  AMENDMENT TO

                AMENDED AND RESTATED INVESTORS' RIGHTS AGREEMENT

         THIS AMENDMENT TO AMENDED AND RESTATED INVESTORS' RIGHTS AGREEMENT
(this "Agreement") is made as of the __ day of ____, 1999, by and among
SALESLOGIX CORPORATION, a Delaware corporation formerly known as Quest Sales
Software, Inc. (the "Company"), and the "Investors", as defined in that certain
Amended and Restated Investors' Rights Agreement dated as of June 4, 1998 (the
"Restated Investors' Rights Agreement") pursuant to Section 3.7 thereof.

                                    RECITALS

         A. As of January 17, 1996, the Company entered into that certain
Investors' Rights Agreement (the "Investors' Rights Agreement") with Innocal,
L.P., Canaan Ventures II Limited Partnership, Canaan Ventures II Offshore
Limited Partnership C.V., and Newtek Ventures II, L.P. (the "Initial Series A
Investors") in connection with the transactions contemplated by that certain
QUEST SALES SOFTWARE, INC. SERIES A PREFERRED STOCK PURCHASE AGREEMENT dated as
of January 17, 1996.

         B. As of October 14, 1996, the Company entered into that certain
Amendment to Investors' Rights Agreement with the Initial Series A Investors and
Deepak Kamra, Morris Ventures and John Purtell (the "Subsequent Series A
Investors") in connection with the transactions contemplated by that certain
SALESLOGIX CORPORATION SECOND SERIES A PREFERRED STOCK PURCHASE AGREEMENT dated
as of October 14, 1996. The Initial Series A Investors and the Subsequent Series
A Investors are referred to herein as the "Series A Investors".

         C. As of March 24, 1997, the Company entered into that certain Second
Amendment to Investors' Rights Agreement with the Initial Series A Investors,
the Subsequent Series A Investors, and Brinson Venture Capital Fund III, L.P.,
Brinson Trust Company as Trustee for the Brinson Map Venture Capital Fund III
Trust, Sigma Partners III, L.P., Sigma Associates III, L.P., Sigma Investors
III, L.P., John R. Mandile, InnoCal, L.P., Canaan Ventures II Limited
Partnership, Canaan Ventures II Offshore Limited Partnership C. V., Newtek
Ventures II, L.P., Comdisco, Inc., Morris Ventures and Deepak Kamra (the "Series
C Investors") in connection with the transactions contemplated by that certain
SALESLOGIX CORPORATION SERIES C STOCK PURCHASE AGREEMENT dated as of March 24,
1997.

         D. As June 4, 1998, the Company entered into the Restated Investors'
Rights Agreement with the Series A Investors, the Series C Investors, and the
investors (the "Series E Investors") set forth on Schedule A to that certain
SALESLOGIX CORPORATION SERIES E PREFERRED STOCK PURCHASE AGREEMENT dated as of
June 4, 1998 and on Schedule A to that certain FOLLOW-ON STOCK PURCHASE
AGREEMENT dated as of December 23, 1998.
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         E. Concurrent with the execution of this Agreement and pursuant to that
certain STOCK PURCHASE AGREEMENT dated as of April 22, 1999 (the "Goldman Stock
Purchase Agreement"), between the Company and The Goldman Sachs Group, L.P., and
certain of its affiliates (collectively, the "Goldman Investors"), the Company,
the Goldman Investors, and a majority in interest of the Series A Investors, the
Series C Investors and the Series E Investors, each as a separate class, wish to
amend the Restated Investors' Rights Agreement, to grant each of the Goldman
Investors all of the rights (and make each of the Goldman Investors subject to
all of the obligations) of Investors under the Restated Investors' Rights
Agreement.

         ACCORDINGLY, in consideration of the mutual covenants contained herein
and other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties to this Agreement agree that the Restated
Investors' Rights Agreement shall be amended as follows:

         1. Goldman Investors. Each Goldman Investor is hereby made a party to
the Restated Investors' Rights Agreement and shall be deemed to be an "Investor"
as defined in the Restated Investors' Rights Agreement for all purposes, and
each Goldman Investor agrees to be bound by all of the obligations of an
Investor thereunder.

         2. Registrable Securities. Section 1.1(f) of the Restated Investors'
Rights Agreement is hereby amended and restated to read in its entirety as
follows:

                  "(f) The term "Registrable Securities" means (i) the Common
         Stock issuable or issued upon conversion of the Company's Series A
         Preferred Stock, Series C Preferred Stock, Series E Preferred Stock
         and, if any Series F Preferred Stock is issued pursuant to the Goldman
         Stock Purchase Agreement, Series F Preferred Stock, (ii) any Common
         Stock issued by the Company pursuant to the Goldman Stock Purchase
         Agreement, and (iii) any Common Stock of the Company issued as (or
         issuable upon the conversion or exercise of any warrant, right or other
         security which is issued as) a dividend or other distribution with
         respect to, or in exchange for, or in replacement of the shares
         referenced in (i) or (ii) above, excluding in all cases, however,
         shares of Common Stock of the Company which have previously been
         registered or which have been sold to the public, or any Registrable
         Securities sold by a person in a transaction in which his rights under
         this Section 1 are not assigned."

         3. Series F Preferred Stock Related Amendments. If the Company issues
Series F Preferred Stock to the Goldman Investors pursuant to the Goldman Stock
Purchase Agreement, then the following provisions shall be amended and restated
to read in their entirety as follows:

                  "2.5(d) The right of first offer in this paragraph 2.5 shall
         not be applicable (i) to the issuance or sale of shares of common stock
         issuable or issued to employees or consultants and advisors of the
         Company (including without limitation independent marketers and
         resellers of the Company's products) directly or pursuant to a stock
         option plan or agreement or restricted stock plan or agreement approved
         by the Board of Directors of the Company at any time when the total
         number of shares of common stock so issuable or issued (and not
         repurchased at cost by the Company in connection with the 


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         termination of employment or service) does not exceed 4,500,000
         (subject to appropriate adjustments for stock splits, stock dividends,
         combinations or other recapitalizations after the effective date of the
         Company's Fifth Restated Certificate of Incorporation), (ii)
         consummation of a bona fide, firmly underwritten public offering of
         shares of common stock, registered under the Act pursuant to a
         registration statement on Form S-1, at an offering price of at least
         $9.00 per share (after giving effect to a reverse stock split effected
         on March 23, 1999, appropriately adjusted for any subsequent stock
         split, dividend, combination or other recapitalization) and $20,000,000
         in the aggregate, (iii) the issuance of securities pursuant to the
         conversion or exercise of convertible or exercisable securities, (iv)
         the issuance of securities to strategic partners of the Company
         primarily for strategic purposes other than raising capital, as so
         reasonably determined by the Board of Directors of the Company, or (v)
         shares of common stock issued in connection with a bona fide lease
         financing transaction approved by the Board of Directors of the
         Company."

                  "2.7 IRC Section 305. So long as any shares of the Company's
         Series A Preferred Stock, Series C Preferred Stock, Series E Preferred
         Stock or Series F Preferred Stock remain outstanding, the Company will
         not, without approval of holders of a majority of the Series A
         Preferred Stock, Series C Preferred Stock, Series E Preferred Stock and
         Series F Preferred Stock then outstanding, voting together on an as
         converted basis, do any act or thing which would result in taxation of
         the holders of shares of the Series A Preferred Stock, Series C
         Preferred, Series E Preferred Stock or Series F Preferred Stock under
         Section 305 of the Internal Revenue Code of 1986, as amended (the
         "IRC") (or any comparable provision of the IRC as hereafter may from
         time to time be amended)."

                  "2.9 Board Committees. So long as any shares of the Company's
         Series A Preferred Stock, Series C Preferred Stock, Series E Preferred
         Stock or Series F Preferred Stock remain outstanding, the Company will
         use its best efforts to have the Board of Directors appoint and
         maintain a Compensation Committee and an Audit Committee. Each such
         Committee shall contain no more than three members and shall include no
         more than one member of management of the Company. The holders of a
         majority of the Series A Preferred Stock, Series C Preferred Stock,
         Series E Preferred Stock and Series F Preferred Stock then outstanding,
         voting together on an as converted basis, shall have the right, but not
         the obligation, to designate two of the members of the Compensation
         Committee."

                  "2.11 Termination of Certain Covenants. The covenants set
         forth in Sections 2.5, 2.7, 2.8 and 2.9 shall terminate and be of no
         further force or effect upon the consummation of the sale of securities
         pursuant to a registration statement filed by the Company under the Act
         in connection with the firm commitment underwritten offering of its
         securities to the general public, provided that such initial public
         offering shall be for not less than $9.00 per share and $20,000,000 in
         the aggregate."


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                 "3.7 Amendments and Waivers. Any term of this Agreement may be
         amended and the observance of any term of this Agreement may be waived
         (either generally or in a particular instance and either retroactively
         or prospectively), only with the written consent of each of (a) the
         Company, (b) the holders of a majority of the Series A Preferred Stock
         of the Company, voting together as a class, (c) the holders of a
         majority of the Series C Preferred Stock of the Company, voting
         together as a class, (d) the holders of a majority of the Series E
         Preferred Stock, voting together as a class, and (e) the holders of a
         majority of the Series F Preferred Stock, voting together as a class.
         Any amendment or waiver effected in accordance with this paragraph
         shall be binding upon each holder of any Registrable Securities then
         outstanding, each future holder of all such Registrable Securities, and
         the Company."

         4. Entire Agreement. The Restated Investors' Rights Agreement, as
amended by this Amendment, constitutes the full and entire understanding and
agreement between the parties with regard to the subjects hereof and thereof.

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.



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                                  THE COMPANY:

                                  SALESLOGIX CORPORATION, a Delaware
                                  corporation



                                  By:       /s/ Gary Acord
                                            ------------------------------------
                                            Gary Acord, CFO and Secretary

                                  Address:  8800 N. Gainey Center Dr., Suite 200
                                            Scottsdale, AZ 85258


                                  INVESTORS:

                                  INNOCAL, L.P., a Delaware Limited Partnership

                                  By:       InnoCal Associates, L.P., a Delaware
                                            Limited Partnership



                                            By:/s/  Harry Lambert
                                               ---------------------------------
                                               Harry Lambert, General Partner

                                  Address:  600 Anton Blvd., Suite 1270
                                            Costa Mesa, CA  92626


                                  CANAAN VENTURES II LIMITED
                                  PARTNERSHIP

                                  By:       Canaan Venture Partners II L.P.



                                            By:/s/  Deepak Kamra
                                               ---------------------------------
                                               Deepak Kamra, General Partner

                                  Address:  2884 Sand Hill Road, Suite 115
                                            Menlo Park, CA 94025


              [SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED
                          INVESTORS' RIGHTS AGREEMENT]


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                                  CANAAN VENTURES II OFFSHORE
                                  LIMITED PARTNERSHIP C.V.

                                  By:       Canaan Venture Partners II L.P.



                                            By:/s/  Deepak Kamra
                                               ---------------------------------
                                               Deepak Kamra, General Partner

                                  Address:  2884 Sand Hill Road, Suite 115
                                            Menlo Park, CA  94025


                                  NEWTEK VENTURES II, L.P.



                                  By:       /s/  John Hall
                                            ------------------------------------
                                            John Hall, General Partner

                                  Address:  500 Washington Street, Suite 720
                                            San Francisco, CA  94111



                                  /s/  Deepak Kamra 
                                  ----------------------------------------------
                                  DEEPAK KAMRA

                                  Address:  2884 Sand Hill Road, Suite 115
                                            Menlo Park, CA  94025


                                  MORRIS VENTURES, a Partnership



                                  By:       /s/  Anthony P. Morris
                                            ------------------------------------
                                            Anthony P. Morris, General Partner

                                  Address:  211 Congress Street, 2nd Floor
                                            Boston, MA  02110


              [SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED
                          INVESTORS' RIGHTS AGREEMENT]


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                                  ----------------------------------------------
                                  JOHN PURTELL

                                  Address:  2750 Northhaven
                                            Dallas, TX  75225


                                  COMDISCO, INC., a Delaware corporation



                                  By:
                                            ------------------------------------
                                            Name:
                                            Its:

                                  Address:  6111 River Road
                                            Rosemont, IL  60018


                                  BRINSON VENTURE CAPITAL FUND III, L.P.

                                  By:       Brinson Partners, Inc., its General
                                            Partner



                                            By:/s/  David S. Timson
                                               ---------------------------------
                                               David S. Timson, Partner

                                  Address:     209 S. LaSalle Street
                                               Chicago, IL 60604




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                          INVESTORS' RIGHTS AGREEMENT]


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                                  BRINSON TRUST COMPANY AS TRUSTEE
                                  FOR THE BRINSON MAP VENTURE
                                  CAPITAL FUND III TRUST



                                  By:       /s/  David S. Timson
                                            ------------------------------------
                                            David S. Timson, Trust Officer

                                  Address:  209 S. LaSalle Street
                                            Chicago, IL 60604


                                  SIGMA PARTNERS III, L.P.,



                                  By:       /s/   Cliff Haas
                                            ------------------------------------
                                            Cliff Haas, General Partner

                                  Address:  2884 Sand Hill Road, Suite 121
                                            Menlo Park, CA  94025


                                  SIGMA ASSOCIATES III, L.P.



                                  By:       /s/  Cliff Haas
                                            ------------------------------------
                                            Cliff Haas, General Partner

                                  Address:  2884 Sand Hill Road, Suite 121
                                            Menlo Park, CA  94025





              [SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED
                          INVESTORS' RIGHTS AGREEMENT]


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                                  SIGMA INVESTORS III, L.P.



                                  By:       /s/  Cliff Haas
                                            ------------------------------------
                                            Cliff Haas, General Partner

                                  Address:  2884 Sand Hill Road, Suite 121
                                            Menlo Park, CA  94025




                                  ----------------------------------------------
                                  JOHN R. MANDILE

                                  Address:  Oak Knoll
                                            Winchester, MA  01890


                                  SIERRA VENTURES VI L.P.



                                  By:  /s/  David C. Schwab
                                       -----------------------------------------
                                       David C. Schwab, General Partner



                                  THE GOLDMAN SACHS GROUP, L.P.



                                  By:  The Goldman Sachs Corporation, its
                                       General Partner


                                       By:/s/  illegible
                                          --------------------------------------
                                          Name:
                                               ---------------------------------
                                          Its:
                                              ----------------------------------




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                          INVESTORS' RIGHTS AGREEMENT]


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                                  STONE STREET FUND 1998, L.P.



                                  By:  Stone Street Advantage Corp.

                                  Its: General Partner


                                       By:/s/ Eve Gerriets
                                          --------------------------------------
                                              Eve Gerriets, Vice President


                                  Address:  85 Broad Street
                                            New York, NY  10004



                                  BRIDGE STREET FUND 1998, L.P.


                                  By:  Bridge Street Advantage Corp.

                                  Its: Managing General Partner



                                       By:/s/ Eve Gerriets
                                          --------------------------------------
                                              Eve Gerriets, Vice President


                                  Address:  85 Broad Street
                                            New York, NY  10004




              [SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED
                          INVESTORS' RIGHTS AGREEMENT]


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                                  CANAAN EQUITY, L.P.



                                  By:  Canaan Equity Partners L.L.C.


                                       By:/s/  Deepak Kamra
                                          --------------------------------------
                                       Deepak Kamra, Member/Manager



                                  ----------------------------------------------
                                  Anthony P. Morris








              [SIGNATURE PAGE TO AMENDMENT TO AMENDED AND RESTATED
                          INVESTORS' RIGHTS AGREEMENT]

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