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REVOLVING LINE OF CREDIT NOTE                                      EXHIBIT 10.15

$500,000.00                     HOUSTON, TEXAS                      JULY 1, 2000

         FOR VALUE RECEIVED, the undersigned, U.S. PHYSICAL THERAPY, INC., A
NEVADA CORPORATION (herein called "MAKER"), promises to pay to the order of
SOUTHWEST BANK OF TEXAS, N.A. (herein called "PAYEE," which term herein in every
instance shall refer to any owner or holder of this note) the sum of FIVE
HUNDRED THOUSAND DOLLARS ($500,000.00), together with interest on the principal
hereof from time to time outstanding from the date of advancement until
maturity, at the per annum rate hereinafter stated (computed on the basis of a
year of 365 days and paid for the actual number of days elapsed), said principal
and interest being payable in lawful money of the United States of America at
the banking quarters of Southwest Bank of Texas, N.A., 4400 Post Oak Park,
Houston, Harris County, Texas, or at such other place as Payee may designate
hereafter in writing.

         This note is issued pursuant to a letter loan agreement of even date
herewith, by and between Maker and Payee (the "LOAN AGREEMENT"), and reference
is made hereby to the Loan Agreement for certain rights as to the prepayment,
the acceleration of the maturity hereof and collateral securing the payment
hereof; and this note is entitled to all the benefits of the Loan Agreement.

         The principal balance hereof advanced and from time to time remaining
unpaid shall bear interest during each day of the term of the loan evidenced
hereby at a variable per annum rate equal to the lesser of (A) a per annum rate
that is equal to (herein called the "BASIC RATE") one-half of one percent (1/2%)
plus the prime rate of interest (herein called the "PRIME RATE"), being the
variable per annum rate of interest most recently announced by Southwest Bank of
Texas, N.A. (herein sometimes called the "BANK") as its "prime rate," with the
understanding that the Bank's "prime rate" may be one of several base rates and
serves as a basis upon which effective rates of interest are from time to time
calculated for loans making reference thereto and may not be the lowest of the
Bank's base rates, which Basic Rate shall change when and as the Prime Rate
shall change, effective on the day of such change or (B) the Maximum Rate
(hereinafter defined). Notwithstanding the foregoing, if at any time the Basic
Rate shall exceed the Maximum Rate and thereafter the Basic Rate shall become
less than the Maximum Rate, the rate of interest payable hereunder shall be the

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Maximum Rate until the Payee shall have received the amount of interest it would
have received otherwise if the interest payable hereunder had not been limited
by the Maximum Rate during the period of time the Basic Rate exceeded the
Maximum Rate.

         All past due principal and interest of this note, whether due as the
result of acceleration of maturity or otherwise, shall bear interest at the
lesser of (1) a rate that is five percentage points above the Prime Rate as it
varies or (2) the maximum lawful rate of interest permitted by the applicable
usury laws, now or hereafter enacted, which interest rate (herein called the
"MAXIMUM RATE") shall change when and as said laws shall change to the extent
permitted by said laws, effective on the day such change in said laws becomes
effective, from the date the payment thereof shall have become due until the
same have been fully discharged by payment.

         The principal and interest of this note are due and payable at the
offices of said Payee in Houston, Harris County, Texas, in accordance with, and
as set forth in, the Loan Agreement.

         Subject to the terms and conditions of the Loan Agreement, the
undersigned may borrow, pay, prepay in whole or in part and, under certain
circumstance set forth in the Loan Agreement, reborrow hereunder, so long as not
more than $500,000.00 of principal is outstanding at any one time; it being
expressly contemplated that, by reason of prepayments hereon, there may be times
when no indebtedness is owing hereunder, but, notwithstanding such occurrences,
this note shall remain valid and shall be in full force and effect as to loans
or advances made subsequent to such occurrences; and it being understood and
agreed that advances and repayments of principal under this note are not limited
to the face amount of principal, but to a maximum of the face amount of
principal at any one time outstanding. In accordance with the Loan Agreement,
Payee may advance funds pursuant to this note from time to time, and from time
to time the undersigned will make repayments on the principal of this note, so
that no more than the face amount of principal shall be outstanding at any one
time. Each advance and each payment of principal hereunder shall be reflected by
a notation made by Payee in its business records. The aggregate unpaid principal
amount of advances reflected by the notations made in Payee's business records
shall be conclusive evidence of the principal amount owing under this note,
which amount the undersigned unconditionally promises to pay to the order of
Payee under the terms hereof.

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         Maker and any and all sureties, guarantors and endorsers of this note
and all other parties now or hereafter liable hereon, severally waive grace,
demand, presentment for payment, protest, notice of any kind (including, but not
limited to, notice of dishonor, notice of protest, notice of intention to
accelerate and notice of acceleration) and diligence in collecting and bringing
suit against any party hereto, and agree (i) to all extensions and partial
payments, with or without notice, before or after maturity, (ii) to any
substitution, exchange or release of any security now or hereafter given for
this note, (iii) to the release of any party primarily or secondarily liable
hereon, and (iv) that it will not be necessary for Payee, in order to enforce
payment of this note, to first institute or exhaust Payee's remedies against
Maker or any other party liable therefor or against any security for this note.

         In the event of default hereunder or under any of the instruments
securing payment hereof and this note is placed in the hands of an attorney for
collection (whether or not suit is filed), or if this note is collected by suit
or legal proceedings or through the probate court or bankruptcy proceedings,
Maker agrees to pay all reasonable attorneys' fees and all expenses of
collection and costs of court.

         It is the intention of the parties hereto to comply with applicable
usury laws; accordingly, Section 10(f) of the Loan Agreement is incorporated
herein by reference and shall have the same force and effect as if set forth
herein.

         This note shall be governed by and construed under the laws of the
State of Texas and applicable United States federal law. This note is subject to
the arbitration provisions under Article 10(d) of the Loan Agreement.

         Any check, draft, money order or other instrument given in payment of
all or any portion hereof may be accepted by Payee and handled in collection in
the customary manner, but the same shall not constitute payment hereunder or
diminish any rights of Payee except to the extent that actual cash proceeds of
such instrument are unconditionally received by Payee.

                                             MAKER:

                                             U.S. PHYSICAL THERAPY, INC., a
                                             Nevada corporation


                                             By:   /s/ J. Michael Mullin
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                                                J. Michael Mullin
                                                Chief Financial Officer


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