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                                                                   EXHIBIT 10.23

                                                                  EXECUTION COPY

      GUARANTY AGREEMENT, dated as of September 30, 2004, made by certain
Subsidiaries (collectively, the "Guarantors", each, a "Guarantor") of BLACKBAUD,
INC., a Delaware corporation (the "Borrower"), in favor of WACHOVIA BANK,
NATIONAL ASSOCIATION, as Administrative Agent (in such capacity, the
"Administrative Agent") for the ratable benefit itself and the financial
institutions (the "Lenders") from time to time parties to the Credit Agreement,
dated of even date herewith (as amended, restated, supplemented or otherwise
modified, the "Credit Agreement"), by and among the Borrower, the Lenders and
the Administrative Agent.

                              STATEMENT OF PURPOSE

      Pursuant to the terms of the Credit Agreement, the Lenders have agreed to
make Extensions of Credit to the Borrower upon the terms and subject to the
conditions set forth therein.

      The Borrower and the Guarantors, though separate legal entities, comprise
one integrated financial enterprise, and all Extensions of Credit to the
Borrower will inure, directly or indirectly, to the benefit of each of the
Guarantors.

      It is a condition precedent to the obligation of the Lenders to make their
respective Extensions of Credit to the Borrower under the Credit Agreement that
the Guarantors shall have executed and delivered this Guaranty to the
Administrative Agent, for the ratable benefit of itself and the Lenders.

      NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged by the parties hereto, and to
induce the Administrative Agent and the Lenders to enter into the Credit
Agreement and to induce the Lenders to make their respective Extensions of
Credit to the Borrower thereunder, each Guarantor hereby agrees with the
Administrative Agent, for the ratable benefit of itself and the Lenders, as
follows:

                                    ARTICLE I

                                  DEFINED TERMS

      SECTION 1.1 Definitions. The following terms when used in this Guaranty
shall have the meanings assigned to them below:

      "Additional Guarantor" means each Subsidiary of the Borrower which
hereafter becomes a Guarantor pursuant to Section 4.17 hereof and Section 8.11
of the Credit Agreement.

      "Applicable Insolvency Laws" means all Applicable Laws governing
bankruptcy, reorganization, arrangement, adjustment of debts, relief of debtors,
dissolution, insolvency,

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fraudulent transfers or conveyances or other similar laws (including, without
limitation, 11 U.S.C. Sections 544, 547, 548 and 550 and other "avoidance"
provisions of Title 11 of the United States Code, as amended or supplemented).

      "Guaranteed Obligations" has the meaning set forth in Section 2.1.

      "Guaranty" means this Guaranty Agreement, as amended, restated,
supplemented or otherwise modified.

      SECTION 1.2 Other Definitional Provisions. Capitalized terms used and not
otherwise defined in this Guaranty including the preambles and recitals hereof
shall have the meanings ascribed to them in the Credit Agreement. In the event
of a conflict between capitalized terms defined herein and in the Credit
Agreement, the Credit Agreement shall control. The words "hereof," "herein",
"hereto" and "hereunder" and words of similar import when used in this Guaranty
shall refer to this Guaranty as a whole and not to any particular provision of
this Guaranty, and Section references are to this Guaranty unless otherwise
specified. The meanings given to terms defined herein shall be equally
applicable to both the singular and plural forms of such terms.

                                   ARTICLE II

                                    GUARANTY

      SECTION 2.1 Guaranty. Each Guarantor hereby, jointly and severally with
the other Guarantors, unconditionally guarantees to the Administrative Agent for
the ratable benefit of itself and the Lenders, and their respective permitted
successors, endorsees, transferees and assigns, the prompt payment and
performance of all Obligations of the Borrower, whether primary or secondary
(whether by way of endorsement or otherwise), whether now existing or hereafter
arising, whether or not from time to time reduced or extinguished (except by
payment thereof) or hereafter increased or incurred, whether or not recovery may
be or hereafter becomes barred by the statute of limitations, whether
enforceable or unenforceable as against the Borrower, whether or not discharged,
stayed or otherwise affected by any Applicable Insolvency Law or proceeding
thereunder, whether created directly with the Administrative Agent or any Lender
or acquired by the Administrative Agent or any Lender through assignment,
endorsement or otherwise, whether matured or unmatured, whether joint or
several, as and when the same become due and payable (whether at maturity or
earlier, by reason of acceleration, mandatory repayment or otherwise), in
accordance with the terms of any such instruments evidencing any such
obligations, including all renewals, extensions or modifications thereof (all
Obligations of the Borrower, including all of the foregoing being hereafter
collectively referred to as the "Guaranteed Obligations").

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      SECTION 2.2 Bankruptcy Limitations on each Guarantor. Notwithstanding
anything to the contrary contained in Section 2.1, it is the intention of each
Guarantor, the Administrative Agent and the Lenders that, in any proceeding
involving the bankruptcy, reorganization, arrangement, adjustment of debts,
relief of debtors, dissolution or insolvency or any similar proceeding with
respect to any Guarantor or its assets, the amount of such Guarantor's
obligations with respect to the Guaranteed Obligations shall be equal to, but
not in excess of, the maximum amount thereof not subject to avoidance or
recovery by operation of Applicable Insolvency Laws after giving effect to
Section 2.3. To that end, but only in the event and to the extent that after
giving effect to Section 2.3 such Guarantor's obligations with respect to the
Guaranteed Obligations or any payment made pursuant to such Guaranteed
Obligations would, but for the operation of the first sentence of this Section
2.2, be subject to avoidance or recovery in any such proceeding under Applicable
Insolvency Laws after giving effect to Section 2.3, the amount of each
Guarantor's obligations with respect to the Guaranteed Obligations shall be
limited to the largest amount which, after giving effect thereto, would not,
under Applicable Insolvency Laws, render such Guarantor's obligations with
respect to the Guaranteed Obligations unenforceable or avoidable or otherwise
subject to recovery under Applicable Insolvency Laws. To the extent any payment
actually made pursuant to the Guaranteed Obligations exceeds the limitation of
the first sentence of this Section 2.2 and is otherwise subject to avoidance and
recovery in any such proceeding under Applicable Insolvency Laws, the amount
subject to avoidance shall in all events be limited to the amount by which such
actual payment exceeds such limitation and the Guaranteed Obligations as limited
by the first sentence of this Section 2.2 shall in all events remain in full
force and effect and be fully enforceable against each Guarantor. The first
sentence of this Section 2.2 is intended solely to preserve the rights of the
Administrative Agent hereunder against each Guarantor in such proceeding to the
maximum extent permitted by Applicable Insolvency Laws and neither such
Guarantor, any Borrower, any other Guarantor nor any other Person shall have any
right or claim under such sentence that would not otherwise be available under
Applicable Insolvency Laws in such proceeding.

      SECTION 2.3 Agreements for Contribution.

      (a) To the extent any Guarantor is required, by reason of its obligations
hereunder, to pay to the Administrative Agent or any Lender an amount greater
than the amount of value (as determined in accordance with Applicable Insolvency
Laws) actually made available to or for the benefit of such Guarantor on account
of the Credit Agreement, this Guaranty or any other Loan Document, such
Guarantor shall have an enforceable right of contribution against the Borrower
and the remaining Guarantors, and the Borrower and the remaining Guarantors
shall be jointly and severally liable for repayment of the full amount of such
excess payment. Subject only to the subordination provided in Section 2.3(d),
such Guarantor further shall be subrogated to any and all rights of the Lenders
against the Borrower and the remaining Guarantors to the extent of such excess
payment.

      (b) To the extent that any Guarantor would, but for the operation of this
Section 2.3 and by reason of its obligations hereunder or its obligations to
other Guarantors under this Section 2.3, be rendered insolvent for any purpose
under Applicable Insolvency Laws, each of the Guarantors hereby agrees to
indemnify such Guarantor and commits to make a contribution to such Guarantor's

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capital in an amount at least equal to the amount necessary to prevent such
Guarantor from having been rendered insolvent by reason of the incurrence of any
such obligations.

      (c) To the extent that any Guarantor would, but for the operation of this
Section 2.3, be rendered insolvent under any Applicable Insolvency Law by reason
of its incurring of obligations to any other Guarantor under the foregoing
Sections 2.3(a) and (b), such Guarantor shall, in turn, have rights of
contribution and indemnity, to the full extent provided in the foregoing
Sections 2.3(a) and (b), against the Borrower and the remaining Guarantors, such
that all obligations of all of the Guarantors hereunder and under this Section
2.3 shall be allocated in a manner such that no Guarantor shall be rendered
insolvent for any purpose under Applicable Insolvency Law by reason of its
incurrence of such obligations.

      (d) Notwithstanding any payment or payments by any of the Guarantors
hereunder, or any set-off or application of funds of any of the Guarantors by
the Administrative Agent or any Lender, or the receipt of any amounts by the
Administrative Agent or any Lender with respect to any of the Guaranteed
Obligations, none of the Guarantors shall be entitled to be subrogated to any of
the rights of the Administrative Agent or any Lender against the Borrower or the
other Guarantors or against any collateral security held by the Administrative
Agent or any Lender for the payment of the Guaranteed Obligations nor shall any
of the Guarantors seek any reimbursement from the Borrower or any of the other
Guarantors in respect of payments made by such Guarantor in connection with the
Guaranteed Obligations, until all amounts owing to the Administrative Agent and
the Lenders on account of the Guaranteed Obligations are paid in full and the
Commitments are terminated. If any amount shall be paid to any Guarantor on
account of such subrogation rights at any time when all of the Guaranteed
Obligations shall not have been paid in full, such amount shall be held by such
Guarantor in trust for the Administrative Agent, segregated from other funds of
such Guarantor, and shall, forthwith upon receipt by such Guarantor, be turned
over to the Administrative Agent in the exact form received by such Guarantor
(duly endorsed by such Guarantor to the Administrative Agent, if required) to be
applied against the Guaranteed Obligations, whether matured or unmatured, in
such order as set forth in the Credit Agreement.

      SECTION 2.4 Nature of Guaranty.

      (a) Each Guarantor agrees that this Guaranty is a continuing,
unconditional guaranty of payment and performance and not of collection, and
that its obligations under this Guaranty shall be primary, absolute and
unconditional, irrespective of, and unaffected by:

            (i) the genuineness, validity, regularity, enforceability or any
      future amendment of, or change in, the Credit Agreement or any other Loan
      Document or any other agreement, document or instrument to which the
      Borrower, any Guarantor or any of their respective Subsidiaries or
      Affiliates is or may become a party;

            (ii) the absence of any action to enforce this Guaranty, the Credit
      Agreement or any other Loan Document or the waiver or consent by the
      Administrative Agent or any Lender with respect to any of the provisions
      of this Guaranty, the Credit Agreement or any other Loan Document;

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            (iii) the existence, value or condition of, or failure to perfect
      its Lien against, any security for or other guaranty of the Guaranteed
      Obligations or any action, or the absence of any action, by the
      Administrative Agent or any Lender in respect of such security or guaranty
      (including, without limitation, the release of any such security or
      guaranty);

            (iv) any structural change in, restructuring of or similar change of
      the Borrower, any Guarantor or any of their respective Subsidiaries; or

            (v) any other action or circumstances which might otherwise
      constitute a legal or equitable discharge or defense of a surety or
      guarantor;

it being agreed by each Guarantor that, subject to the first sentence of Section
2.2, its obligations under this Guaranty shall not be discharged until the final
indefeasible payment and performance, in full, of the Guaranteed Obligations and
the termination of the Commitments; provided that a Guarantor may be released
from the Guaranteed Obligations pursuant to Section 4.16 of this Guaranty.

      (b) Each Guarantor represents, warrants and agrees that its obligations
under this Guaranty are not and shall not be subject to any counterclaims,
offsets or defenses of any kind against the Administrative Agent, the Lenders or
the Borrower whether now existing or which may arise in the future.

      (c) Each Guarantor hereby agrees and acknowledges that the Guaranteed
Obligations, and any of them, shall conclusively be deemed to have been created,
contracted or incurred, or renewed, extended, amended or waived, in reliance
upon this Guaranty, and all dealings between the Borrower and any Guarantor, on
the one hand, and the Administrative Agent and the Lenders, on the other hand,
likewise shall be conclusively presumed to have been had or consummated in
reliance upon this Guaranty.

      SECTION 2.5 Waivers. To the extent permitted by law, each Guarantor
expressly waives all of the following rights and defenses (and agrees not to
take advantage of or assert any such right or defense):

      (a) any rights it may now or in the future have under any statute, or at
law or in equity, or otherwise, to compel the Administrative Agent or any Lender
to proceed in respect of the Obligations against the Borrower or any other
Person or against any security for or other guaranty of the payment and
performance of the Guaranteed Obligations before proceeding against, or as a
condition to proceeding against, such Guarantor;

      (b) any defense based upon the failure of the Administrative Agent or any
Lender to commence an action in respect of the Guaranteed Obligations against
the Borrower, any Guarantor or any other Person or any security for the payment
and performance of the Guaranteed Obligations;

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      (c) any right to insist upon, plead or in any manner whatever claim or
take the benefit or advantage of, any appraisal, valuation, stay, extension,
marshalling of assets or redemption laws, or exemption, whether now or at any
time hereafter in force, which may delay, prevent or otherwise affect the
performance by such Guarantor of its obligations under, or the enforcement by
the Administrative Agent or the Lenders of this Guaranty;

      (d) any right of diligence, presentment, demand, protest and notice
(except as specifically required herein) of whatever kind or nature with respect
to any of the Guaranteed Obligations and waives, to the extent permitted by
Applicable Laws, the benefit of all provisions of law which are or might be in
conflict with the terms of this Guaranty; and

      (e) any and all right to notice of the creation, renewal, extension or
accrual of any of the Obligations and notice of or proof of reliance by the
Administrative Agent or any Lender upon, or acceptance of, this Guaranty.

      Each Guarantor agrees that any notice or directive given at any time to
the Administrative Agent or any Lender which is inconsistent with any of the
foregoing waivers shall be null and void and may be ignored by the
Administrative Agent or such Lender, and, in addition, may not be pleaded or
introduced as evidence in any litigation relating to this Guaranty for the
reason that such pleading or introduction would be at variance with the written
terms of this Guaranty, unless the Administrative Agent and the Required Lenders
have specifically agreed otherwise in writing. The foregoing waivers are of the
essence of the transaction contemplated by the Credit Agreement and the other
Loan Documents and, but for this Guaranty and such waivers, the Administrative
Agent and Lenders would decline to enter into the Credit Agreement and the other
Loan Documents.

      SECTION 2.6 Modification of Loan Documents, etc. Neither the
Administrative Agent nor any Lender shall incur any liability to any Guarantor
as a result of any of the following, and none of the following shall impair or
release this Guaranty or any of the obligations of any Guarantor under this
Guaranty:

      (a) any change or extension of the manner, place or terms of payment of,
or renewal or alteration of all or any portion of, the Guaranteed Obligations;

      (b) any action under or in respect of the Credit Agreement or the other
Loan Documents in the exercise of any remedy, power or privilege contained
therein or available to any of them at law, in equity or otherwise, or waiver or
refrain from exercising any such remedies, powers or privileges;

      (c) any amendment or modification, in any manner whatsoever, of the Credit
Agreement or any other Loan Document;

      (d) any extension or waiver of the time for performance by the Borrower,
any Guarantor or any other Person of, or compliance with, any term, covenant or
agreement on its part to be performed or observed under the Credit Agreement or
any other Loan Document, or

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waive such performance or compliance or consent to a failure of, or departure
from, such performance or compliance;

      (e) any taking and holding of security or collateral for the payment of
the Obligations or the sale, exchange, release, disposal of, or other dealing
with, any property pledged, mortgaged or conveyed, or in which the
Administrative Agent or the Lenders have been granted a Lien, to secure any
Indebtedness of the Borrower, any Guarantor or any other Person to the
Administrative Agent or the Lenders;

      (f) any release of anyone who may be liable in any manner for the payment
of any amounts owed by the Borrower, any Guarantor or any other Person to the
Administrative Agent or any Lender;

      (g) any modification or termination of the terms of any intercreditor or
subordination agreement pursuant to which claims of other creditors of the
Borrower, any Guarantor or any other Person are subordinated to the claims of
the Administrative Agent or any Lender; or

      (h) any application of any sums by whomever paid or however realized to
any Obligations owing by the Borrower, any Guarantor or any other Person to the
Administrative Agent or any Lender in such manner as the Administrative Agent or
any Lender shall determine in its reasonable discretion.

      SECTION 2.7 Demand by the Administrative Agent. In addition to the terms
set forth in this Article II and in no manner imposing any limitation on such
terms, if all or any portion of the then outstanding Guaranteed Obligations
under the Credit Agreement are declared to be immediately due and payable, then
the Guarantors shall, upon demand in writing therefor by the Administrative
Agent to the Guarantors, pay all or such portion of the outstanding Guaranteed
Obligations due hereunder then declared due and payable. Notwithstanding the
foregoing, each Guarantor agrees that, in the event of the dissolution or
insolvency of the Borrower or any Guarantor, or the inability or failure of the
Borrower or any Guarantor to pay debts as they become due, or an assignment by
the Borrower or any Guarantor for the benefit of creditors, or the commencement
of any case or proceeding in respect of the Borrower or any Guarantor under
bankruptcy, insolvency or similar laws, and if such event shall occur at a time
when any of the Guaranteed Obligations may not then be due and payable, each
Guarantor will pay to the Administrative Agent, for the ratable benefit of the
Lenders and their respective successors, indorsees, transferees and assigns,
forthwith the full amount which would be payable hereunder by each Guarantor if
all such Guaranteed Obligations were then due and payable.

      SECTION 2.8 Remedies. Upon the occurrence and during the continuance of
any Event of Default, with the consent of the Required Lenders, the
Administrative Agent may, or upon the request of the Required Lenders, the
Administrative Agent shall, enforce against the Guarantors their respective
obligations and liabilities hereunder and exercise such other rights and
remedies as may be available to the Administrative Agent hereunder, under the
Credit Agreement or the other Loan Documents or otherwise.

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      SECTION 2.9 Benefits of Guaranty. The provisions of this Guaranty are for
the benefit of the Administrative Agent and the Lenders and their respective
permitted successors, transferees, endorsees and assigns, and nothing herein
contained shall impair, as between the Borrower, the Administrative Agent and
the Lenders, the obligations of the Borrower under the Credit Agreement and the
other Loan Documents. In the event all or any part of the Obligations are
transferred, endorsed or assigned by the Administrative Agent or any Lender to
any Person or Persons as permitted under the Credit Agreement, any reference to
an "Administrative Agent", or "Lender" herein shall be deemed to refer equally
to such Person or Persons.

      SECTION 2.10 Termination; Reinstatement.

      (a) Subject to subsection (c) below, this Guaranty shall remain in full
force and effect until all the Guaranteed Obligations and all the obligations of
the Guarantors shall have been paid in full and the Commitments terminated.

      (b) No payment made by the Borrower, any Guarantor, or any other Person
received or collected by the Administrative Agent or any Lender from the
Borrower, any Guarantor, or any other Person by virtue of any action or
proceeding or any set-off or appropriation or application at any time or from
time to time in reduction of or in payment of the Guaranteed Obligations shall
be deemed to modify, reduce, release or otherwise affect the liability of any
Guarantor hereunder which shall, notwithstanding any such payment (other than
any payment made by such Guarantor in respect of the obligations of the
Guarantors or any payment received or collected from such Guarantor in respect
of the obligations of the Guarantors), remain liable for the obligations of the
Guarantors up to the maximum liability of such Guarantor hereunder until the
Guaranteed Obligations and all the obligations of the Guarantors shall have been
paid in full and the Commitments terminated.

      (c) Each Guarantor agrees that, if any payment made by the Borrower or any
other Person applied to the Obligations is at any time annulled, set aside,
rescinded, invalidated, declared to be fraudulent or preferential or otherwise
required to be refunded or repaid by the Administrative Agent or any Lender to
the Borrower, its estate, trustee, receiver or any other Person, including,
without limitation, any Guarantor, under any Applicable Law or equitable cause,
then, to the extent of such payment or repayment, each Guarantor's liability
hereunder shall be and remain in full force and effect, as fully as if such
payment had never been made, and, if prior thereto, this Guaranty shall have
been canceled or surrendered, this Guaranty shall be reinstated in full force
and effect, and such prior cancellation or surrender shall not diminish,
release, discharge, impair or otherwise affect the obligations of such Guarantor
in respect of the amount of such payment.

      SECTION 2.11 Payments. Payments by the Guarantors shall be made to the
Administrative Agent, to be credited and applied to the Guaranteed Obligations
in accordance with Sections 4.4 and 11.4 of the Credit Agreement, in immediately
available Dollars to an account designated by the Administrative Agent or at the
Administrative Agent's Office or at any other address that may be specified in
writing from time to time by the Administrative Agent.

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                                   ARTICLE III

                         REPRESENTATIONS AND WARRANTIES

      To induce the Administrative Agent and the Lenders to make any Extensions
of Credit each Guarantor hereby represents and warrants that:

      SECTION 3.1 Existence. Such Guarantor is duly organized, validly existing
and in good standing under the laws of the jurisdiction of its incorporation or
formation, has the power and authority to own its properties and to carry on its
business as now being and hereafter proposed to be conducted and is duly
qualified and authorized to do business in each jurisdiction in which the
character of its properties or the nature of its business requires such
qualification and authorization except where the failure to be so qualified
would not have a Material Adverse Effect.

      SECTION 3.2 Authorization of Agreement; Enforceability. Such Guarantor has
the right, power and authority and has taken all necessary corporate or other
action to authorize the execution, delivery and performance of this Guaranty in
accordance with its terms. This Guaranty has been duly executed and delivered by
the duly authorized officers of such Guarantor and this Guaranty constitutes the
legal, valid and binding obligation of such Guarantor enforceable in accordance
with its terms, except as such enforceability may be limited by bankruptcy,
insolvency, reorganization, moratorium or similar state or federal debtor relief
laws from time to time in effect which affect the enforcement of creditors'
rights in general and the availability of equitable remedies.

      SECTION 3.3 No Conflict; Consents. The execution, delivery and performance
by such Guarantor of this Guaranty in accordance with its terms and the
transactions contemplated hereby do not and will not, by the passage of time,
the giving of notice or otherwise, (i) require any Governmental Approval or
violate any Applicable Law relating to such Guarantor; (ii) conflict with,
result in a breach of or constitute a default under the articles of
incorporation, bylaws or other organizational documents of such Guarantor or any
indenture, agreement or other instrument to which such Person is a party or by
which any of its properties may be bound or any Governmental Approval relating
to such Person, (iii) result in or require the creation or imposition of any
Lien upon or with respect to any property now owned or hereafter acquired by
such Guarantor or (iv) require any consent or authorization of, filing with, or
other act in respect of, an arbitrator or Governmental Authority and no consent
of any other Person is required in connection with the execution, delivery,
performance, validity or enforceability of this Guaranty.

      SECTION 3.4 Litigation. Except for matters existing on the Closing Date
and set forth on Schedule 6.1(u) to the Credit Agreement, and except for matters
existing in the ordinary course that could not reasonably be expected,
individually, or in the aggregate, to have a Material Adverse Effect, there are
no actions, suits or proceedings pending nor, to the knowledge of such
Guarantor, threatened against or in any way relating adversely to or affecting
such Guarantor or any its respective properties in any court or before any
arbitrator of any kind or before or by any Governmental Authority.

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      SECTION 3.5 Title to Assets. Such Guarantor has such title to the real
property owned or leased by it as is necessary or desirable to the conduct of
its business and valid and legal title to all of its personal property and
assets. None of the properties and assets of such Guarantor is subject to any
Lien, except Permitted Liens. No financing statement under the Uniform
Commercial Code of any state which names such Guarantor or any of its respective
trade names or divisions as debtor and which has not been terminated, has been
filed in any state or other jurisdiction and such Guarantor has not signed any
such financing statement or any security agreement authorizing any secured party
thereunder to file any such financing statement, except to perfect Permitted
Liens.

      SECTION 3.6 Solvency. Subject in each case to the first sentence of
Section 2.2, as of the Closing Date (or such later date upon which such
Guarantor became a party hereto), and after giving effect to the transactions
contemplated hereby, such Guarantor will be Solvent.

      SECTION 3.7 Compliance with the Credit Agreement. Until the Obligations
shall have been paid in full and the Commitments terminated, such Guarantor
shall comply with the provisions of Articles VII, VIII, IX and X of the Credit
Agreement as if a party thereto.

                                   ARTICLE IV

                                  MISCELLANEOUS

      SECTION 4.1 Amendments, Waivers and Consents. None of the terms,
covenants, agreements or conditions of this Guaranty may be amended,
supplemented or otherwise modified, nor may they be waived, nor may any consent
be given, except in accordance with Section 13.2 of the Credit Agreement.

      SECTION 4.2 Notices. All notices and communications hereunder shall be
given to the addresses and otherwise made in accordance with Section 13.1(a) of
the Credit Agreement; provided that notices and communications to the Guarantors
shall be directed to the Guarantors at the address of the Borrower set forth in
Section 13.1(b) of the Credit Agreement.

      SECTION 4.3 Enforcement Expenses, Indemnification.

      (a) Each Guarantor agrees to pay or reimburse each Lender and the
Administrative Agent for all its reasonable costs and expenses actually incurred
in connection with the administration or enforcement of any rights and remedies
of the Administrative Agent and the Lenders under this Guaranty and the other
Loan Documents to which such Guarantor is a party, including, without
limitation, in connection with any workout, restructuring, bankruptcy or other
similar proceeding enforcing any Guaranteed Obligations of, or collecting any
payments due from, such Guarantor by reason of an Event of Default, consulting
with appraisers, accountants, engineers, attorneys and other Persons concerning
the nature, scope or value of any right or remedy of the Administrative Agent or
any Lender under this Guaranty or under any other Loan Document or any factual
matters in connection therewith, which expenses shall include without

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limitation the reasonable fees and disbursements of such Persons. All such costs
and expenses shall be additional Guaranteed Obligations.

      (b) Each Guarantor agrees to defend, indemnify and hold harmless the
Administrative Agent and the Lenders, and their respective parents,
Subsidiaries, Affiliates, employees, agents, officers and directors, from and
against any losses, penalties, fines, liabilities, settlements, damages, costs
and expenses, suffered by any such Person in connection with any claim
(including, without limitation, any Environmental Claims), investigation,
litigation or other proceeding (whether or not the Administrative Agent or any
Lender is a party thereto) and the prosecution and defense thereof, arising out
of or in any way connected with this Guaranty to the extent the Borrower would
be required to do so pursuant to Section 13.3 of the Credit Agreement.

      (c) The agreements in this Section 4.3 shall survive termination of the
Commitments and repayment of the Obligations and all other amounts payable under
the Credit Agreement and the other Loan Documents.

      SECTION 4.4 Governing Law. This Guaranty, unless otherwise expressly set
forth herein, shall be governed by, construed and enforced in accordance with
the laws of the State of North Carolina, without reference to the conflicts or
choice of law principles thereof.

      SECTION 4.5 Jurisdiction and Venue.

      (a) Jurisdiction. Each Guarantor hereby irrevocably consents to the
personal jurisdiction of the state and federal courts located in Mecklenburg
County, North Carolina (and any courts from which an appeal from any of such
courts must or may be taken) in any action, claim or other proceeding arising
out of any dispute in connection with this Guaranty, any rights or obligations
hereunder, or the performance of such rights and obligations. Each Guarantor
hereby irrevocably consents to the service of a summons and complaint and other
process in any action, claim or proceeding brought by the Administrative Agent
or any Lender in connection with this Guaranty, any rights or obligations
hereunder, or the performance of such rights and obligations, on behalf of
itself or its property, in the manner specified in Section 13.1 of the Credit
Agreement. Nothing in this Section 4.5 shall affect the right of the
Administrative Agent or any Lender to serve legal process in any other manner
permitted by Applicable Law or affect the right of the Administrative Agent or
any Lender to bring any action or proceeding against any Guarantor or its
properties in the courts of any other jurisdictions.

      (b) Venue. Each Guarantor hereby irrevocably waives any objection it may
have now or in the future to the laying of venue in the aforesaid jurisdiction
in any action, claim or other proceeding arising out of or in connection with
this Guaranty or the rights and obligations of the parties hereunder. Each
Guarantor irrevocably waives, in connection with such action, claim or
proceeding, any plea or claim that the action, claim or proceeding has been
brought in an inconvenient forum.

      SECTION 4.6 Binding Arbitration; Waiver of Jury Trial.

                                                                      2248204.04
                                                                  LIB: CHARLOTTE

                                       11
<PAGE>

      (a) Binding Arbitration. Upon demand of any party, whether made before or
after institution of any judicial proceeding, any Dispute between or among
parties hereto shall be resolved by binding arbitration as provided herein.
Institution of a judicial proceeding by a party does not waive the right of that
party to demand arbitration hereunder. Disputes may include, without limitation,
tort claims, counterclaims, claims brought as class actions, claims arising from
Loan Documents executed in the future, disputes as to whether a matter is
subject to arbitration, or claims concerning any aspect of the past, present or
future relationships arising out of or connected with the Loan Documents.
Arbitration shall be conducted under and governed by the Arbitration Rules of
the AAA and the Federal Arbitration Act. All arbitration hearings shall be
conducted in Charlotte, North Carolina. The expedited procedures set forth in
Rule 51, et seq. of the Arbitration Rules shall be applicable to claims of less
than $1,000,000. All applicable statutes of limitations shall apply to any
Dispute. A judgment upon the award may be entered in any court having
jurisdiction. Notwithstanding anything foregoing to the contrary, any
arbitration proceeding demanded hereunder shall begin within ninety (90) days
after such demand thereof and shall be concluded within one hundred twenty (120)
days after such demand. These time limitations may not be extended unless a
party hereto shows cause for extension and then such extension shall not exceed
a total of sixty (60) days. The panel from which all arbitrators are selected
shall be comprised of licensed attorneys selected from the Commercial Financial
Dispute Arbitration Panel of the AAA. The single arbitrator selected for
expedited procedure shall be a retired judge from the highest court of general
jurisdiction, state or federal, of the state where the hearing will be
conducted. The parties hereto do not waive any applicable Federal or state
substantive law except as provided herein. Notwithstanding the foregoing, this
paragraph shall not apply to any Hedging Agreement.

      (b) Jury Trial. EACH PARTY HERETO HEREBY ACKNOWLEDGES THAT BY AGREEING TO
BINDING ARBITRATION THEY HAVE IRREVOCABLY WAIVED THEIR RESPECTIVE RIGHTS TO A
JURY TRIAL WITH RESPECT TO ANY ACTION, CLAIM OR OTHER PROCEEDING ARISING OUT OF
ANY DISPUTE IN CONNECTION WITH THIS GUARANTY, ANY RIGHTS OR OBLIGATIONS
HEREUNDER, OR THE PERFORMANCE OF SUCH RIGHTS AND OBLIGATIONS.

      (c) Preservation of Certain Remedies. Notwithstanding the preceding
binding arbitration provisions, the parties hereto and the other Loan Documents
preserve, without diminution, certain remedies that such Persons may employ or
exercise freely, either alone, in conjunction with or during a Dispute. Each
such Person shall have and hereby reserves the right to proceed in any court of
proper jurisdiction or by self help to exercise or prosecute the following
remedies, as applicable: (i) all rights to foreclose against any real or
personal property or other security by exercising a power of sale granted in the
Loan Documents or under Applicable Law or by judicial foreclosure and sale,
including a proceeding to confirm the sale, (ii) all rights of self help
including peaceful occupation of property and collection of rents, set off, and
peaceful possession of property, (iii) obtaining provisional or ancillary
remedies including injunctive relief, sequestration, garnishment, attachment,
appointment of receiver and in filing an involuntary bankruptcy proceeding, and
(iv) when applicable, a judgment by confession of judgment. Preservation of
these remedies does not limit the power of an arbitrator to grant similar
remedies that may be requested by a party in a Dispute.

                                                                      2248204.04
                                                                  LIB: CHARLOTTE

                                       12
<PAGE>

      SECTION 4.7 Injunctive Relief, Punitive Damages.

      (a) Each Guarantor recognizes that, in the event such Guarantor fails to
perform, observe or discharge any of its obligations or liabilities under this
Guaranty, any remedy of law may prove to be inadequate relief to the
Administrative Agent and the Lenders. Therefore, each Guarantor agrees that the
Administrative Agent and the Lenders, at their option, shall be entitled to
temporary and permanent injunctive relief in any such case without the necessity
of proving actual damages.

      (b) The Administrative Agent and each Guarantor hereby agree that no such
Person shall have a remedy of punitive or exemplary damages against any other
party to this Guaranty, the Credit Agreement, the Notes or the other Loan
Documents and each such Person hereby waives any right or claim to punitive or
exemplary damages that they may now have or may arise in the future in
connection with any Dispute, whether such Dispute is resolved through
arbitration or judicially.

      SECTION 4.8 No Waiver by Course of Conduct, Cumulative Remedies. Neither
the Administrative Agent nor any Lender shall by any act (except by a written
instrument pursuant to Section 4.1), delay, indulgence, omission or otherwise be
deemed to have waived any right or remedy hereunder or to have acquiesced in any
Default or Event of Default. No delay or failure to take action on the part of
the Administrative Agent or any Lender in exercising any right, power or
privilege shall operate as a waiver thereof, nor shall any single or partial
exercise of any such right, power or privilege preclude any other or further
exercise thereof or the exercise of any other right, power or privilege or shall
be construed to be a waiver of any Event of Default. No course of dealing
between any Guarantor, the Administrative Agent and any Lenders or their
respective agents or employees shall be effective to change, modify or discharge
any provision of this Guaranty or to constitute a waiver of any Event of
Default. The enumeration of the rights and remedies of the Administrative Agent
and the Lenders set forth in this Guaranty is not intended to be exhaustive and
the exercise by the Administrative Agent and the Lenders of any right or remedy
shall not preclude the exercise of any other rights or remedies, all of which
shall be cumulative, and shall be in addition to any other right or remedy given
hereunder or under the other Loan Documents or that may now or hereafter exist
at law or in equity or by suit or otherwise.

                                                                      2248204.04
                                                                  LIB: CHARLOTTE

                                       13
<PAGE>

      SECTION 4.9 Successors and Assigns. This Guaranty shall be binding upon
each Guarantor and its successors and assigns and shall inure to the benefit of
each Guarantor (and shall bind all Persons who become bound as a Guarantor under
this Guaranty), the Administrative Agent and the Lenders and their successors
and assigns; provided that no Guarantor may assign, transfer or delegate any of
its rights or obligations under this Guaranty without the prior written consent
of the Administrative Agent and the Lenders (given in accordance with Section
4.1).

      SECTION 4.10 Severability. Any provision of this Guaranty which is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective only to the extent of such prohibition or unenforceability
without invalidating the remainder of such provision or the remaining provisions
hereof or thereof or affecting the validity or enforceability of such provision
in any other jurisdiction.

      SECTION 4.11 Titles and Captions. Titles and captions of Articles,
      Sections and subsections in, and the table of contents of, this Guaranty
are for convenience only, and neither limit nor amplify the provisions of this
Guaranty.

      SECTION 4.12 Counterparts. This Guaranty may be executed in any number of
counterparts and by different parties hereto in separate counterparts, each of
which when so executed shall be deemed to be an original and shall be binding
upon all parties, their successors and assigns, and all of which taken together
shall constitute one and the same agreement.

      SECTION 4.13 Set-Off. Each Guarantor hereby irrevocably authorizes the
Administrative Agent and each Lender at any time and from time to time pursuant
to Section 13.4 of the Credit Agreement to set-off and appropriate and apply any
and all deposits (general or special, time or demand, provisional or final), in
any currency, and any other credits, indebtedness or claims, in any currency, in
each case whether direct or indirect, absolute or contingent, matured or
unmatured, at any time held or owing by the Administrative Agent or such Lender
to or for the credit or the account of such Guarantor, or any part thereof in
such amounts as the Administrative Agent or such Lender may elect, against and
on account of the obligations and liabilities of such Guarantor to the
Administrative Agent or such Lender hereunder and claims of every nature and
description of the Administrative Agent or such Lender against such Guarantor,
in any currency, whether arising hereunder, under the Credit Agreement, any
other Loan Document or otherwise, as the Administrative Agent or such Lender may
elect, whether or not the Administrative Agent or any Lender has made any demand
for payment and although such obligations, liabilities and claims may be
contingent or unmatured. The Administrative Agent and each Lender shall notify
such Guarantor promptly of any such set-off and the application made by the
Administrative Agent or such Lender of the proceeds thereof; provided that the
failure to give such notice shall not affect the validity of such set-off and
application. The rights of the Administrative Agent and each Lender under this
Section 4.13 are in addition to other rights and remedies (including, without
limitation, other rights of set-off) which the Administrative Agent or such
Lender may have.

                                                                      2248204.04
                                                                  LIB: CHARLOTTE

                                       14
<PAGE>

      SECTION 4.14. Integration. This Guaranty, together with the other Loan
Documents, comprises the complete and integrated agreement of the parties on the
subject matter hereof and thereof and supersedes all prior agreements, written
or oral, on such subject matter. This Guaranty was drafted with the joint
participation of the respective parties thereto and shall be construed neither
against nor in favor of any party, but rather in accordance with the fair
meaning thereof.

      SECTION 4.15. Acknowledgements. Each Guarantor hereby acknowledges that:

      (a) it has been advised by counsel in the negotiation, execution and
delivery of this Guaranty and the other Loan Documents to which it is a party;

      (b) neither the Administrative Agent nor any Lender has any fiduciary
relationship with or duty to any Guarantor arising out of or in connection with
this Guaranty or any of the other Loan Documents, and the relationship between
the Guarantors, on the one hand, and the Administrative Agent and Lenders, on
the other hand, in connection herewith or therewith is solely that of debtor and
creditor; and

      (c) no joint venture is created hereby or by the other Loan Documents or
otherwise exists by virtue of the transactions contemplated hereby among the
Lenders or among the Guarantors and the Lenders.

      SECTION 4.16. Releases. At such time as (a) the Guaranteed Obligations
shall have been paid in full and the Commitments have been terminated, this
Guaranty and all obligations (other than those expressly stated to survive such
termination) of the Administrative Agent and each Guarantor hereunder shall
terminate, all without delivery of any instrument or performance of any act by
any party, or (b) a Guarantor ceases to be a Material Subsidiary of the Borrower
in connection with a transaction permitted under the terms and conditions of the
Credit Agreement, such Guarantor shall be released from the Guaranteed
Obligations (other than obligations expressly stated to survive the termination
of this Guaranty).

      SECTION 4.17 Additional Guarantors. Each Material Subsidiary of the
Borrower that is required to become a party to this Guaranty pursuant to Section
8.11 of the Credit Agreement shall become a Guarantor for all purposes of this
Guaranty upon execution and delivery by such Subsidiary of a supplement in form
and substance satisfactory to the Administrative Agent.

      SECTION 4.18 Powers Coupled with an Interest. All authorizations and
agencies herein contained are irrevocable and powers coupled with an interest.

                           [Signature Pages to Follow]

                                                                      2248204.04
                                                                  LIB: CHARLOTTE

                                       15
<PAGE>

      IN WITNESS WHEREOF, each of the Guarantors has executed and delivered this
Guaranty under seal by their duly authorized officers, all as of the day and
year first above written.

                              BLACKBAUD, LLC, as Guarantor

                              By: /s/ Timothy V. Williams
                                  ----------------------------------------------
                                    Name: Timothy V. Williams
                                    Title: Vice President and CFO

                           [Signature Pages Continue]

[Guaranty Agreement]
<PAGE>

                              WACHOVIA BANK, NATIONAL
                               ASSOCIATION, as Administrative Agent

                              By: /s/ John D. Brady
                                  ----------------------------------------------
                                    Name: John D. Brady
                                    Title: Director

[Guaranty Agreement]

<PAGE>

===============================================================================

                               GUARANTY AGREEMENT

                         dated as of September 30, 2004

                                  by and among

                    certain Subsidiaries of BLACKBAUD, INC.,
                                 as Guarantors,

                                   in favor of

                      WACHOVIA BANK, NATIONAL ASSOCIATION,
                             as Administrative Agent

===============================================================================
<PAGE>

                                TABLE OF CONTENTS

<TABLE>
<S>                                                                                <C>
ARTICLE I  DEFINED TERMS........................................................   1
SECTION 1.1   Definitions........................................................  1

ARTICLE II   GUARANTY...........................................................   2
SECTION 2.1   Guaranty.........................................................    2
SECTION 2.2   Bankruptcy Limitations on each Guarantor.........................    3
SECTION 2.3   Agreements for Contribution......................................    3
SECTION 2.4   Nature of Guaranty...............................................    4
SECTION 2.5   Waivers..........................................................    5
SECTION 2.6   Modification of Loan Documents, etc..............................    6
SECTION 2.7   Demand by the Administrative Agent...............................    7
SECTION 2.8   Remedies.........................................................    7
SECTION 2.9   Benefits of Guaranty.............................................    8
SECTION 2.10  Termination; Reinstatement........................................   8
SECTION 2.11  Payments..........................................................   8

ARTICLE III.....................................................................   9

REPRESENTATIONS AND WARRANTIES..................................................   9
SECTION 3.1   Existence........................................................    9
SECTION 3.2   Authorization of Agreement; Enforceability.......................    9
SECTION 3.3   No Conflict; Consents............................................    9
SECTION 3.4   Litigation.......................................................    9
SECTION 3.5   Title to Assets..................................................   10
SECTION 3.6   Solvency.........................................................   10
SECTION 3.7   Compliance with the Credit Agreement.............................   10

ARTICLE IV  MISCELLANEOUS.......................................................  10
SECTION 4.1   Amendments, Waivers and Consents.................................   10
SECTION 4.2   Notices..........................................................   10
SECTION 4.3   Enforcement Expenses, Indemnification............................   10
SECTION 4.4   Governing Law....................................................   11
SECTION 4.5   Jurisdiction and Venue...........................................   11
SECTION 4.6   Binding Arbitration; Waiver of Jury Trial........................   11
SECTION 4.7   Injunctive Relief, Punitive Damages..............................   13
SECTION 4.8   No Waiver by Course of Conduct, Cumulative Remedies..............   13
SECTION 4.9   Successors and Assigns...........................................   14
SECTION 4.10  Severability......................................................  14
SECTION 4.11  Titles and Captions...............................................  14
SECTION 4.12  Counterparts......................................................  14
SECTION 4.13  Set-Off...........................................................  14
SECTION 4.14. Integration.......................................................  15
SECTION 4.15. Acknowledgements..................................................  15
SECTION 4.16. Releases..........................................................  15
SECTION 4.17  Additional Guarantors.............................................  15
</TABLE>