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                                                                   EXHIBIT 10.19

                       THIRD AMENDMENT TO CREDIT AGREEMENT


     THIS THIRD AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is entered into
as of September 30, 2002, among PMC COMMERCIAL TRUST, a real estate investment
trust organized under the laws of the State of Texas ("Borrower"), certain
Lenders, and BANK ONE, NA, a national banking association with its main office
in Chicago, Illinois, successor by merger to Bank One, Texas, N.A.
("Administrative Agent").

                             PRELIMINARY STATEMENT:

     Borrower, Administrative Agent and Lenders are party to that certain Credit
Agreement (as renewed, extended, amended and restated, the "Credit Agreement")
dated as of November 29, 1999, pursuant to which the Lenders have made and may
hereafter make loans to Borrower. Concurrently herewith, Midfirst Bank and Texas
Capital Bank, N.A. are assigning all of their rights and interests as Lenders
under the Credit Agreement to Bank One, NA. Borrower, Administrative Agent and
Bank One, NA, as sole remaining Lender after the assignments described above,
have agreed to amend the Credit Agreement in order to (i) reduce the Commitment
and Bank One, NA's Committed Sum to $30,000,000, and (ii) extend the Stated
Termination Date to March 22, 2003.

     Accordingly, for adequate and sufficient consideration, the receipt of
which is hereby acknowledged, Borrower, Administrative Agent and Lenders agree
as follows:

     1. Defined Terms; References. Unless otherwise stated in this Amendment (a)
terms defined in the Credit Agreement have the same meanings when used in this
Amendment and (b) references to "Sections," "Schedules" and "Exhibits" are to
sections, schedules and exhibits to the Credit Agreement.

     2. Amendments.

          (a)  The defined term "Commitment" in Section 1.1 of the Credit
               Agreement is amended in its entirety as follows:

               "Commitment" means an amount (subject to reduction or
               cancellation as herein provided) equal to $30,000,000.

          (b)  The defined term "Stated Termination Date" in Section 1.1 of the
               Credit Agreement is amended in its entirety as follows:

               "Stated Termination Date" means March 22, 2003.

          (c)  Schedule 2 to the Credit Agreement is hereby amended in its
               entirety as set forth on Annex A attached hereto.

     3. Conditions Precedent. Notwithstanding any contrary provisions, the
foregoing paragraphs in this Amendment are not effective unless and until (a)
the representations and warranties in this Amendment are true and correct, (b)
Lender receives counterparts of this

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Amendment executed by each party named below, (c) the assignments of interests
contemplated by the Preliminary Statement above have been completed, and (d)
Borrower executes and delivers to Bank One, NA a renewal and replacement
Revolving Note in the maximum principal amount of $30,000,000.

     4. Ratifications. This Amendment modifies and supersedes all inconsistent
terms and provisions of the Credit Documents, and except as expressly modified
and superseded by this Amendment, the Credit Documents are ratified and
confirmed and continue in full force and effect. Borrower, Administrative Agent
and Lenders agree that the Credit Documents, as amended by this Amendment,
continue to be legal, valid, binding and enforceable in accordance with their
respective terms. Without limiting the generality of the foregoing, Borrower
hereby ratifies and confirms that all Liens heretofore granted to Administrative
Agent on behalf of the Lenders were intended to, do, and continue to secure the
full payment and performance of the Obligation. Borrower agrees to perform such
acts and duly authorize, execute, acknowledge, deliver, file and record such
additional assignments, security agreements, modifications or amendments to any
of the foregoing, and such other agreements, documents, and instruments as
Administrative Agent or Lenders may reasonably request in order to perfect and
protect those Liens and preserve and protect the rights of Administrative Agent
and Lenders in respect of all present and future Collateral.

     5. Representations and Warranties. Borrower hereby represents and warrants
to Administrative Agent and Lenders that (a) this Amendment and any Credit
Documents to be delivered under this Amendment have been duly executed and
delivered by Borrower, (b) no action of, or filing with, any Governmental
Authority is required to authorize, or is otherwise required in connection with,
the execution, delivery, and performance by Borrower of this Amendment and any
Credit Document to be delivered under this Amendment, (c) this Amendment and any
Credit Documents to be delivered under this Amendment are valid and binding upon
Borrower and are enforceable against Borrower in accordance with their
respective terms, except as limited by any applicable Debtor Relief Laws, (d)
the execution, delivery and performance by Borrower of this Amendment and any
Credit Documents to be delivered under this Amendment do not require the consent
of any other Person and do not and will not constitute a violation of any
Governmental Requirements, agreements or understandings to which Borrower is a
party or by which Borrower is bound, (e) the representations and warranties
contained in the Credit Agreement, as amended by this Amendment, and any other
Credit Document are true and correct in all material respects as of the date of
this Amendment, and (f) as of the date of this Amendment, no Event of Default or
Potential Default exists or is imminent.

     6. References. All references in the Credit Documents to the "Credit
Agreement" refer to the Credit Agreement as amended by this Amendment. This
Amendment is a "Credit Document" referred to in the Credit Agreement and the
provisions relating to Credit Documents in the Credit Agreement are incorporated
by reference, the same as if set forth verbatim in this Amendment.

     7. Counterparts. This Amendment may be executed in any number of
counterparts with the same effect as if all signatories had signed the same
document.


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     8. Parties Bound. This Amendment binds and inures to the benefit of
Borrower, Administrative Agent and each Lender, and, subject to Section 14 of
the Credit Agreement, their respective successors and assigns.

     9. Entirety. THIS AMENDMENT, THE CREDIT AGREEMENT AS AMENDED BY THIS
AMENDMENT, AND THE OTHER CREDIT DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN
THE PARTIES FOR THE TRANSACTIONS THEREIN, AND MAY NOT BE CONTRADICTED BY
EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENT BETWEEN THE
PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENT BETWEEN THE PARTIES.

     EXECUTED as of the date first stated above.

                                   BANK ONE, NA,
                                   as Administrative Agent and a Lender


                                   By:
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                                          Bradley C. Peters, Vice President


                                   PMC COMMERCIAL TRUST,
                                   as Borrower


                                   By:
                                       ---------------------------------------
                                   Name:
                                         -------------------------------------
                                   Title:
                                          ------------------------------------




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