Exhibit 10.1

                          AMENDMENT AGREEMENT NO. 1 TO
                   THIRD AMENDED AND RESTATED CREDIT AGREEMENT

      THIS AMENDMENT  AGREEMENT (the "Amendment  Agreement") is made and entered
into this 8th day of October,  2004, among RADIATION THERAPY  SERVICES,  INC., a
Florida  corporation  (the  "Borrower"),  each  Subsidiary  Guarantor party to a
Subsidiary  Guaranty  pursuant to the terms of the Credit  Agreement (as defined
below),  BANK OF AMERICA,  N.A., as  Administrative  Agent (the  "Administrative
Agent"),  and the  Lenders  party to the Credit  Agreement.  Unless the  context
otherwise  requires,  capitalized  terms used but not  defined  herein  have the
meanings ascribed thereto in the Credit Agreement.

                              W I T N E S S E T H:

      WHEREAS,  the  Borrower,  the  Administrative  Agent and the Lenders  have
entered into that certain Third Amended and Restated  Credit  Agreement dated as
of March  31,  2004,  (as the same may be  modified,  supplemented,  amended  or
amended and restated  from time to time,  the "Credit  Agreement"),  whereby the
Lenders have made available to the Borrower a term loan A facility,  a term loan
B facility and a revolving  credit facility with a letter of credit  subfacility
and a swing line subfacility; and

      WHEREAS,  the  Borrower  desires to prepay the Term Loan B in full and has
requested  that the Term Loan A Lenders  readvance  a portion of the Term Loan A
and that the Revolving  Lenders increase their  commitments  under the Revolving
Credit Facility; and

      WHEREAS,  the Revolving  Lenders are willing to increase their commitments
under the Revolving  Credit  Facility and the Term Loan A Lenders are willing to
readvance  $13,750,000  of the Term Loan A, the  proceeds of which will be used,
together with funds drawn under the  Revolving  Credit  Facility,  to prepay the
Term Loan B in full; and

      WHEREAS,  the  Administrative  Agent,  the  Lenders and the  Borrower  are
willing to amend the Credit Agreement in the manner described herein and subject
to the terms and conditions set forth herein; and

      NOW, THEREFORE,  the Borrower, the Administrative Agent and the Lenders do
hereby agree as follows:

      1. Credit Agreement. The term "Credit Agreement" as used herein and in the
Credit  Documents  (as  defined in the Credit  Agreement)  shall mean the Credit
Agreement as hereby amended and modified.

      2.  Amendment.  Subject to the  conditions  set forth  herein,  the Credit
Agreement is hereby amended, effective as of the date hereof, as follows:


                                       4
<PAGE>

      (a) Section 1.1 of the Credit Agreement is amended to add a new subsection
(e) to the end thereof, which shall read as follows:

            (e) The parties hereto acknowledge that, notwithstanding clauses (c)
      and (d) above, and  notwithstanding the provisions  regarding  assignments
      set forth in Section  14.7  hereof,  as of the  Amendment  No. 1 Effective
      Date,  the  Term  Loan  A  Commitment,  Revolving  Credit  Commitment  and
      Applicable  Commitment  Percentage  for each of the Revolving  Lenders and
      Term Loan A Lenders are as follows:

Term Loan A Facility

<TABLE>
<CAPTION>
                                                               Term Loan A       Portion of Term
                                                           Outstandings prior     Loan A being
                                                                   to            readvanced as of      Applicable
                                          Term Loan A        Amendment No. 1     the Amendment No.     Commitment
Term Loan A Lender                        Commitment         Effective Date      1 Effective Date      Percentage
<S>                                     <C>                 <C>                  <C>                  <C>
Bank of America, N.A.                   $  6,109,022.54     $  3,552,631.66      $  3,359,962.40      24.436090160%
Wachovia Bank, National Association     $  5,865,516.04     $  2,529,904.36      $  3,226,033.82      23.462064160%
Fifth Third Bank, Florida               $  4,316,188.18     $  2,368,421.10      $  2,373,903.50      17.264752720%
SunTrust Bank                           $  3,352,130.38     $  1,776,315.60      $  1,843,671.71      13.408521520%
Regions Bank                            $  2,976,190.48     $    511,363.64      $  1,636,904.76      11.904761920%
National City Bank                      $  2,380,952.38     $    511,363.64      $  1,309,523.81       9.523809520%
Term Loan A Facility Total              $ 25,000,000.00

Revolving Loan Facility

                                                                                                        Applicable
                                        Revolving Credit                                                Commitment
Revolving Lender                           Commitment                                                   Percentage

Bank of America, N.A.                   $ 19,548,872.11                                               24.436090150%
Wachovia Bank, National Association     $ 18,769,651.33                                               23.462064163%
Fifth Third Bank, Florida               $ 13,811,802.19                                               17.264752738%
SunTrust Bank                           $ 10,726,817.22                                               13.408521525%
Regions Bank                            $  9,523,809.52                                               11.904761900%
National City Bank                      $  7,619,047.62                                                9.523809525%
Revolving Credit Facility Total         $ 80,000,000.00
TOTAL FACILITIES                        $105,000,000.00
                                        ===============
</TABLE>

      (b) Section 1.2 of the Credit  Agreement  is amended to add the  following
definitions in the appropriate alphabetical order:

            "Amendment  No. 1" means that certain  Amendment  Agreement No. 1 to
      Third Amended and Restated  Credit  Agreement dated as of October 8, 2004,
      by


                                       5
<PAGE>

      and among the Borrower,  the  Subsidiary  Guarantors,  the  Administrative
      Agent and the Lenders party thereto.

            "Amendment  No. 1 Effective  Date" means the date all the conditions
      to the  effectiveness  of  Amendment  No.  1  contained  in  Section  4 of
      Amendment No. 1 are satisfied.

      (c) Section 1.2 of the Credit  Agreement  is further  amended to amend and
restate in their entirety the  definitions of  "Applicable  Margin  Percentage",
"Cash Equivalents", "EBITDA", "Revolving Notes", "Term Loan A Commitment", "Term
Loan A Facility",  "Term Loan A Notes" and "Total Revolving Credit  Commitments"
to read as follows:

            "Applicable  Margin  Percentage"  shall  mean,  at any time from and
      after the Amendment No. 1 Effective  Date, with respect to Revolving Loans
      and Segments of the Term Loan A and the commitment fee payable pursuant to
      Section 5.2(a), the applicable  percentage set forth below, each (i) to be
      added to the Base Rate pursuant to Section 5.1 for purposes of determining
      the Adjusted Base Rate, and (ii) to be added to the LIBOR Rate pursuant to
      Section 5.1 for purposes of determining the Adjusted LIBOR Rate:

<TABLE>
<CAPTION>
                                                  Applicable Margin      Applicable Margin
                                                      Percentage            Percentage
            Leverage Ratio                       for Base Rate Loans     for LIBOR Loans
            --------------                       -------------------     ---------------

            <S>                                        <C>                     <C>
            Less than 1.50 to 1.00                     0.25%                   1.75%
            Greater  than or  equal  to 1.50           0.50%                   2.00%
                to 1.00,  but less than 2.00
                to 1.00
            Greater  than or  equal  to 2.00           0.75%                   2.25%
                to 1.00,  but less than 2.50
                to 1
            Greater  than or  equal  to 2.50           1.125%                  2.625%
                to 1.00 but less  than  2.75
                to 1.00
            Greater  than or  equal  to 2.75           1.50%                   3.00%
                to 1.00
</TABLE>

            On each  Adjustment Date (as  hereinafter  defined),  the Applicable
      Margin  Percentage  for  all  Revolving  Loans  and  Term  Loan A and  the
      commitment  fee  payable  pursuant  to Section  5.2(a)  shall be  adjusted
      effective  as of such date (based  upon the  calculation  of the  Leverage
      Ratio as of the last day of the  fiscal  period to which  such  Adjustment
      Date relates) in  accordance  with the above  matrix;  provided,  however,
      that,  notwithstanding  the  foregoing  or  anything  else  herein  to the
      contrary,  if at any time the  Borrower  shall have  failed to deliver the
      financial  statements and a Compliance  Certificate as required by Section
      9.1(a) or Section 9.1(b), as the case may be, and Section 9.2(a),  then at
      the election of the Required  Revolving Lenders and the Required Term Loan
      A Lenders, at all times


                                       6
<PAGE>

      from and  including  the  date on which  such  statements  and  Compliance
      Certificate  are required to have been  delivered to the date on which the
      same shall have been delivered each Applicable  Margin Percentage shall be
      determined  in accordance  with the above matrix as if the Leverage  Ratio
      were greater than 2.75:1.00  (notwithstanding  the actual Leverage Ratio).
      For purposes of this definition, "Adjustment Date" shall mean with respect
      to any fiscal  period of the Borrower  beginning  with the fiscal  quarter
      ending  December 31, 2004,  the tenth (10th) day (or, if such day is not a
      Business Day, on the next  succeeding  Business Day) after delivery by the
      Borrower in  accordance  with Section  9.1(a),  Section  9.1(b) or Section
      9.9(b),  as the case may be, of (i) financial  statements as of the end of
      and for such fiscal period, (ii) a duly completed  Compliance  Certificate
      with  respect to such fiscal  period,  and (iii) any pro forma  Compliance
      Certificate  of the  Borrower  and its  Subsidiaries  giving  effect  to a
      Permitted Acquisition in accordance with Section 9.9."


            "Cash  Equivalents"  shall mean Eligible  Investments of High Credit
      Quality  without  Concentrations  and  with a  Short  Term  Maturity.  For
      purposes of this definition:


            1)    Eligible   Investments   are  defined  as  investment  in  the
                  following  held in U.S.  dollars:  (i) AAA rated money  market
                  mutual funds;  (ii)  obligations  issued by the U.S.  Treasury
                  such as treasury bills,  treasury notes and/or treasury bonds;
                  (iii)  obligations  issued  by a U.S.  Federal  Agency  (e.g.,
                  Federal  Home Loan Bank,  Federal  Farm Credit Bank and Fannie
                  Mae); (iv) obligations of major  corporations and bank holding
                  companies and limited to commercial  paper,  corporate  notes,
                  corporate  bonds  and   medium-term-notes;   (v)  taxable  and
                  tax-exempt municipal  securities,  which also include variable
                  rate demands notes (VRDNs) and auction rate  securities;  (vi)
                  auction  rate  preferreds;   or  (vii)  repurchase  agreements
                  collateralized  by U.S.  Treasury  or agency  securities  at a
                  minimum level of 102%.

            2)    High Credit Quality is defined as: (i) investments  which bear
                  a short-term  credit rating must have a minimum  rating and be
                  explicitly rated by two of the rating services as follows:  A1
                  by  Standard & Poor's,  P1 by Moody's  and/or F-1 by Fitch (no
                  split-rated paper permitted) - for municipal  securities,  the
                  short-term credit minimum must be SPI by S&P, MIG1 by Moody's;
                  (ii)  investments  which bear a long-term  credit  rating must
                  have a minimum  rating and be  explicitly  rated by two of the
                  rating  services  as follows:  A by  Standard & Poor's,  A2 by
                  Moody's and/or A by Fitch; or (iii) investments,  which bear a
                  AAA-rating,  need  only be  rated by one of the  three  rating
                  agencies.

            3)    Concentration  is defined as the  portfolio  holding more than
                  10% of its  portfolio in one issue or more than 10% of any one
                  issuer. AAA-rated


                                       7
<PAGE>

                  money market  mutual  funds,  U.S.  Treasury  and U.S.  Agency
                  securities are exempt from these concentration limits.

            4)    Short Term  Maturity  is defined as  investments  that  mature
                  within six months.  For investments where the interest rate is
                  adjusted  via an  auction,  the  auction  date will be used to
                  determine liquidity.

            "EBITDA"  shall mean,  for any period,  (A) the aggregate of (i) net
      income (or loss) of a Person for such  period,  determined  in  accordance
      with GAAP, plus (ii) the sum of interest expense, taxes,  depreciation and
      amortization of such Person for such Period, determined in accordance with
      GAAP, plus (iii) the write-off of any deferred financing costs as a result
      of the  execution  and  effectiveness  of  Amendment  No. 2 to the  Second
      Amended  Credit  Agreement,  this  Agreement,  and Amendment No. 1 to this
      Agreement  but,  in the case of both (ii) and  (iii),  only to the  extent
      deducted in determining net income for the applicable period.

            "Revolving Notes" means,  collectively,  the promissory notes of the
      Borrower  evidencing   Revolving  Loans  executed  and  delivered  to  the
      Revolving  Lenders as provided in Section 3.4 substantially in the form of
      Exhibit A-2, with appropriate insertions as to amounts, dates and names of
      the Revolving Lenders, including any amendments and restatements thereof.

            "Term Loan A Commitment"  shall mean, with respect to each Term Loan
      A Lender,  the  obligation  of such  Lender to make the Term Loan A to the
      Borrower  in  a  principal  amount  equal  to  such  Lender's   Applicable
      Commitment  Percentage of the Total Term Loan A Commitment as set forth in
      (i) after the  Effective  Date and prior to the  Amendment No. 1 Effective
      Date,  Section  1.1(c),  and  (ii) as of and  after  the  Amendment  No. 1
      Effective Date, Section 1.1(e).

            "Term Loan A Facility" shall mean the facility  described in Section
      2.1 providing for a Term Loan A to the Borrower by the Term Loan A Lenders
      in  the  principal   amount  of  $25,000,000,   $11,250,000  of  which  is
      outstanding prior to the effectiveness of Amendment No. 1 hereto.

            "Term Loan A Notes" means, collectively, the promissory notes of the
      Borrower  evidencing  the Term Loan A executed  and  delivered to the Term
      Loan A Lenders as  provided in Section  2.4  substantially  in the form of
      Exhibit A-1, with appropriate insertions as to amounts, dates and names of
      the  Term  Loan A  Lenders,  including  any  amendments  and  restatements
      thereof.

            "Total  Revolving Credit  Commitment"  shall mean a principal amount
      equal  to  $80,000,000,  as  reduced  or  increased  from  time to time in
      accordance with Section 3.5 or 3.6.

      (d)  Section  1.2 is  amended to delete the  definitions  of "Excess  Cash
Flow",  "Shareholders'  Agreement" and "Shareholder  Life Insurance  Payment" in
their entirety.  All references in the Agreement to such terms shall be null and
void.


                                       8
<PAGE>

      (e)  Section  2.1(b)  is  hereby  amended  to  delete  each  reference  to
"$1,250,000" contained therein and replace it with "$1,750,000".

      (f) Section 2.1 is further  amended to add a new subsection (c) to the end
thereof as follows:

            (c) The Borrower hereby  acknowledges  that the Term Loan A has been
      advanced and is outstanding  in the principal  amount of $11,250,000 as of
      the Amendment No. 1 Effective Date (but immediately prior to giving effect
      to such Amendment No. 1). Notwithstanding anything contained herein to the
      contrary,  including  but not limited to any  prohibitions  on  subsequent
      advances  contained in subsection (a) above, the Term Loan A Lenders agree
      to  readvance  $13,750,000  of the  Term  Loan A to  the  Borrower  on the
      Amendment  No. 1 Effective  Date (the  "Amendment  No. 1 Advance"),  which
      Amendment No. 1 Advance shall be used  exclusively  to prepay a portion of
      the Term Loan B in accordance with Section 2.3(b)(v).  The Amendment No. 1
      Advance  shall  advanced  as a Base Rate  Segment on the  Amendment  No. 1
      Effective Date,  without  additional notice or consent,  including without
      any Notice of  Borrowing,  and the entire  proceeds of the Amendment No. 1
      Advance shall be applied immediately by the Administrative Agent, together
      with $9,010,000 to be drawn under the Revolving Credit Facility, to prepay
      the outstanding amount of the Term Loan B ($22,760,000) in full. After the
      Amendment  No. 1  Effective  Date and such  Amendment  No. 1 Advance,  the
      principal amount of each Segment of the Term Loan A outstanding  hereunder
      from  time to time  shall  bear  interest  and the  Term  Loan A shall  be
      repayable as herein provided. After the Amendment No. 1 Effective Date, no
      amount  of the Term  Loan A  repaid  or  prepaid  by the  Borrower  may be
      reborrowed  hereunder,  and no  subsequent  advances  of the  Term  Loan A
      amounts shall be made by any Lender after the Amendment No. 1 Advance.

      (g) Section  2.3(a) is hereby  amended to delete the  introductory  phrase
"The  Borrower may prepay the Term Loan A and the Term Loan B, but only on a pro
rata  basis  based  upon the Pro Rata  Percentages,"  and to replace it with the
phrase "The Borrower may prepay the Term Loan A or the Term Loan B,".

      (h)  Section  9.1(a)  is  amended  to  provide  that  quarterly  financial
statements  shall be  delivered to the  Administrative  Agent not later than the
earlier of the date required to be delivered to the SEC or forty-five  (45) days
after the end of each of the first three fiscal quarters of each fiscal year.

      (i)   Section  9.1(b) is amended and  restated in its  entirety to read as
            follows:

                  (b) not later than the earlier of the date when required to be
            delivered  to the SEC or  ninety  (90)  days  after  the end of each
            fiscal year of the  Borrower,  a  consolidated  balance sheet of the
            Borrower and its Subsidiaries  (including all Excluded Subsidiaries)
            as at the end of such  fiscal  year,  and the  related


                                       9
<PAGE>

            consolidated  statements  of  income  or  operations,  shareholders'
            equity and cash flows for such fiscal  year,  setting  forth in each
            case in comparative  form the figures for the previous  fiscal year,
            all in  reasonable  detail and  prepared  in  accordance  with GAAP,
            audited  and  accompanied  by a report and opinion of Ernst & Young,
            LLP or other  independent  certified public accountant of nationally
            recognized standing  reasonably  acceptable to the Required Lenders,
            which  report and  opinion  shall be  prepared  in  accordance  with
            generally  accepted  auditing  standards and shall not be subject to
            any "going concern" or exception or any  qualification  or exception
            as to the scope of such audit.

            (j) Section 9.2 is amended as follows:

            (a)  subsection  (a) is amended to delete  the  introductory  phrase
      "Concurrently with each delivery of the financial  statements described in
      Section 9.1 (except, for the auditor's draft financial statements provided
      for in  subsection  (b)  thereof)"  and to replace it with the phrase "Not
      later than  forty-five  (45) days after the end of each of the first three
      fiscal  quarters of each fiscal year of the Borrower and one hundred (100)
      days after the end of each fiscal year of the Borrower (except in the case
      of the Compliance  Certificate and related Covenant Compliance  Worksheet,
      which shall be delivered concurrently with the delivery by the Borrower of
      its financial statements to the SEC),";

            (b)  subsection  (b) is amended to delete  the  introductory  phrase
      "Concurrently with the delivery of the financial  statements  described in
      Section  9.1(b),"  and to replace  it with the phrase  "Not later than one
      hundred  (100) days after the end of each fiscal  year of the  Borrower,";
      and

            (c)  subsection  (c) is deleted in its entirety in and replaced with
      the following: "(c) Intentionally deleted.".

      (k) Section  9.9(a)(ii) is amended and restated in its entirety to read as
follows:

            (ii) the  Required  Lenders  shall have given their  consent to such
      acquisition  which consent shall (A) not be unreasonably  withheld and (B)
      be given within ten (10)  Business  Days from the  Administrative  Agent's
      receipt of the  information,  in form and  substance  satisfactory  to the
      Administrative Agent in its reasonable discretion,  referred to in clauses
      (b) and (c) of this  Section  9.9;  provided  that no such consent will be
      required  if the  Acquisition  Amount  with  respect  to such  acquisition
      (regardless   of  the  form  of   consideration)   (y)  shall  not  exceed
      $12,000,000,  and (z)  together  with  the  aggregate  of the  Acquisition
      Amounts  (regardless of the form of consideration) for all other Permitted
      Acquisitions  consummated  during the same fiscal  year,  shall not exceed
      $25,000,000  (including any "earnout"  payments made such fiscal year with
      respect to any Permitted Acquisition,  irrespective of when such Permitted
      Acquisition was consummated).

      (l) Section 9.9(b)(iii) is amended and restated in its entirety to read as
follows:


                                       10
<PAGE>

            (iii) consolidated  projected income statement of the Target and its
      subsidiaries  for  the  two-year  period  following  consummation  of such
      Permitted Acquisition, in reasonable detail, together with any appropriate
      statement of assumptions and pro forma adjustments; and

      (m) Section  9.15 is amended to delete such  section in its  entirety  and
replace it as follows:

          9.15 Intentionally Deleted.

      (n) Section  9.16 is amended to delete such  section in its  entirety  and
replace it as follows:

          9.16 Intentionally Deleted.

      (o) Section 11.2 is amended to delete "and" at the end of subsection (vii)
thereof,  delete "." at the end of subsection (viii) thereof and replace it with
";" and add the following subsection (ix) to read as follows:

            (ix) (A)  Indebtedness  of the  Borrower or any  Subsidiary,  not to
      exceed $15,000,000 in the aggregate,  owing to the seller(s) in connection
      with one or more Permitted  Acquisitions,  provided that such Indebtedness
      is  unsecured  and,  subordinated  in right and time of  payment  upon the
      occurrence  of an Event of  Default  hereunder,  and shall have such other
      terms  (including  but not  limited  to a 180 day  standstill  provision),
      conditions and provisions reasonably satisfactory in form and substance to
      the Administrative  Agent and (B) Contingent  Obligations  permitted under
      Section 11.16(v).

      (p) Section  11.5(x) is amended to replace the number  "$1,000,000" in the
second line thereof and replace it with "$2,000,000.

      (q) Section 11.4 is amended to delete "and" at the end of subsection  (vi)
thereof,  delete "." at the end of subsection  (vii) thereof and replace it with
";" and add the following subsection (viii) to read as follows:

            (viii)  dispositions  by the  Borrower  or any  Subsidiary  of  real
      property  pursuant  to  sale-leaseback  transactions,  provided  that such
      property  was  acquired for the purpose of  constructing  or  renovating a
      cancer  radiation  facility thereon for sale and leaseback to the Borrower
      or any Subsidiary,  and including without  limitation any such transaction
      in which either the end  purchaser/lessor  under such  transaction  or the
      Borrower  or  any  such   Subsidiary   funds  the   construction   of  the
      improvements,   and  further   provided  that  (A)  such   disposition  is
      consummated  within  180  days  of  the  issuance  of the  certificate  of
      occupancy  for  such  facility,  (B) the  sale  proceeds  received  by the
      Borrower   or   Subsidiary,   as   applicable,   are  not  less  than  the
      Borrower/Subsidiary's actual cost of acquisition and construction for such
      facility,  and (C) the sale proceeds from such disposition are used within
      five days of receipt thereof to prepay Revolving Credit Outstandings.


                                       11
<PAGE>

      (r) Effective as of September 30, 2004, Section 11.10 is amended to delete
the  reference  to   "$15,000,000"   contained   therein  and  replace  it  with
"$25,000,000."

      (s) Section 11.6 is amended to delete in their entirety  clauses (iv), (v)
and (viii) thereof and re-number clauses (vi) and (vii) as appropriate.

      (t) Section 11.8 is amended to amend and restate the last sentence thereof
in its entirety to read as follows:

            "Notwithstanding  the  foregoing,  Financial  Services of  Southwest
      Florida,  Inc.  may engage in the  business  of  providing  administrative
      services for the Borrower and its  Subsidiaries;  Radiation Therapy School
      for Radiation  Therapy  Technology,  Inc. may operate a radiation  therapy
      school for the  Borrower  and its  Subsidiaries;  and Devoto  Construction
      Company  of  Southwest  Florida,  Inc.  may  engage  in  the  business  of
      construction of radiation facilities to be operated by the Borrower or any
      of its Subsidiaries;  provided that, the primary focus of the Borrower and
      its Subsidiaries continues to be providing radiation oncology services.

      (u)  Section  11.16 is amended to change the  reference  in the sixth line
thereof from  "$1,000,000" to "$3,000,000"  and to amend and restated clause (v)
in its entirety to read as follows:

      (v)  Contingent  Obligations  owing  to a  seller  in  connection  with  a
Permitted Acquisition, which Contingent Obligations are unsecured and shall have
terms,  conditions and provisions reasonably  satisfactory in form and substance
to the Administrative Agent.

      3.  Representations,   Warranties  and  Covenants.   The  Borrower  hereby
represents, warrants and covenants that:

            (a) The  representations  and  warranties  made by the  Borrower  in
      Article  VIII of the  Credit  Agreement  are  true  on and as of the  date
      hereof;

            (b)  There has been no  Material  Adverse  Change in the  condition,
      financial or otherwise, of the Borrower since the Effective Date;

            (c) The business and properties of the Borrower are not and have not
      been adversely  affected in any substantial way as the result of any fire,
      explosion,  earthquake, accident, strike, lockout, combination of workers,
      flood,  embargo,  riot,  activities of armed forces, war or acts of God or
      the public enemy, or cancellation or loss of any major contracts; and

            (d) No event has occurred and no condition exists which  constitutes
      a Default  or an Event of Default  on the part of the  Borrower  under the
      Credit   Agreement,   the  Notes  or  any  other  Credit  Document  either
      immediately or with the lapse of time or the giving of notice, or both.


                                       12
<PAGE>

      4.  Conditions.  This Amendment  Agreement shall become effective upon the
Borrower  delivering  to  the  Administrative  Agent  the  following;  provided,
however,  upon such  delivery,  the  amendment  set forth in Section 2(r) hereof
shall be deemed effective as of September 30, 2004:

            (a) ten (10) counterparts of this Amendment  Agreement duly executed
      by the Administrative  Agent, the Lenders, the Borrower and the Subsidiary
      Guarantors;

            (b) a certificate of the secretary or an assistant secretary of each
      of the  Borrower  and each  Subsidiary  Guarantor,  in form and  substance
      satisfactory to the Administrative Agent, certifying (i) that the articles
      or certificate of incorporation or articles or certificate of organization
      of the Borrower or such Subsidiary Guarantor, as the case may be, have not
      been amended  since such  articles or  certificate  were  delivered on the
      Effective  Date or attaching  any  amendments  thereto since the Effective
      Date,  as each may be  certified  as of a recent date by the  Secretary of
      State  (or  comparable  Governmental  Authority)  of its  jurisdiction  of
      organization,  (ii)  that the  bylaws,  operating  agreement,  partnership
      agreement or other comparable  document of the Borrower or such Subsidiary
      Guarantor,  as the case may be, have not been  amended  since such bylaws,
      operating  agreement,  partnership  agreement or other comparable document
      was  delivered on the Effective  Date,  and that such document has been in
      effect at all times from the date on which the resolutions  referred to in
      clause  (iii)  below  were  adopted  to and  including  the  date  of such
      certificate,  and (iii) that attached  thereto is a true and complete copy
      of  resolutions  adopted  by the  board of  directors,  managers,  general
      partners  or  other  comparable  governing  body of the  Borrower  or such
      Subsidiary  Guarantor,  as the case  may be,  authorizing  the  execution,
      delivery and  performance of this  Amendment  Agreement and the amendments
      contemplated  herein,  and as to the  incumbency  and  genuineness  of the
      signature of each officer of the Borrower or such Subsidiary Guarantor, as
      the case may be,  executing  this Amendment  Agreement,  and attaching all
      such copies of the documents described above;

            (c) amendments or modifications to the existing  Mortgages,  in form
      and substance reasonably  satisfactory to the Administrative  Agent, dated
      as of the date hereof and duly  executed  by the  Borrower,  a  Subsidiary
      Guarantor and the trustee thereunder, as applicable, together in each case
      with the Mortgaged  Property  Support  Documents and any additional  title
      policy endorsements required by the Administrative Agent in its reasonable
      discretion;

            (d) all fees and expenses  payable by the Borrower by reason of this
      Amendment Agreement;

            (e) such other documentation,  instruments,  consents and agreements
      as the  Administrative  Agent shall  reasonably  request  including  those
      described in paragraph 8 of this Amendment Agreement;


                                       13
<PAGE>

            (f) amended and  restated or  replacement  Revolving  Notes for each
      Revolving  Lender whose  Revolving  Credit  Commitment  is increasing as a
      result of this Amendment Agreement and amended and restated or replacement
      Term Loan A Notes  reflecting the re-advance of a portion of the Term Loan
      A pursuant to this Amendment Agreement; and

            (g) irrevocable  notice shall have been given to the  Administrative
      Agent  that  the  Term  Loan B will be  prepaid  in full on or  about  the
      Amendment  No. 1 Effective  Date but in any event not later than the third
      Business Day following the Amendment No. 1 Effective  Date,  with proceeds
      of the  Amendment No. 1 Advance and  $9,010,000  drawn under the Revolving
      Credit Facility.

      5. Consent to Interest  Period.  The Lenders hereby consent and agree that
in connection  with the Amendment No. 1 Effective  Date, the Borrower may make a
one-time  request for an Interest Period for Loans of other than one, two, three
or six months in length;  provided that such  Interest  Period shall begin on or
about the Amendment No. 1 Effective Date and shall end on December 31, 2004.

      6.  Entire  Agreement.  This  Amendment  Agreement  sets  forth the entire
understanding  and  agreement  of the parties  hereto in relation to the subject
matter hereof and supersedes  any prior  negotiations  and agreements  among the
parties relative to such subject matter. None of the terms or conditions of this
Amendment  may be changed,  modified,  waived or canceled  orally or  otherwise,
except as provided in the Credit Agreement.

      7. Full  Force  and  Effect of  Agreement.  Except as hereby  specifically
amended,  modified or  supplemented,  the Credit  Agreement and all of the other
Credit  Documents  are hereby  confirmed  and ratified in all respects and shall
remain in full force and effect according to their respective terms.

      8. Counterparts. This Amendment Agreement may be executed in any number of
counterparts  and all  the  counterparts  taken  together  shall  be  deemed  to
constitute one and the same instrument.

      9.   Documentation.   All  instruments  and  documents   incident  to  the
consummation of the  transactions  contemplated  hereby shall be satisfactory in
form  and  substance  to  the   Administrative   Agent  and  its  counsel;   the
Administrative  Agent shall have received  copies of all additional  agreements,
instruments  and  documents  which  it  may  reasonably  request  in  connection
therewith,  including  copies of  resolutions of the Borrowers  authorizing  the
transactions  contemplated by this Amendment  Agreement,  such  documents,  when
appropriate,   to  be  certified  by  appropriate   corporate  or   governmental
authorities;  and  all  proceedings  of the  Borrower  relating  to the  matters
provided for herein shall be  satisfactory to the  Administrative  Agent and its
counsel.

      10.  Entire  Agreement.  This  Amendment  Agreement  sets forth the entire
understanding  and  agreement  of the parties  hereto in relation to the subject
matter hereof and supersedes  any prior  negotiations  and agreements  among the
parties relative to such subject matter. No promise, conditions,  representation
or  warranty,  express or  implied,  not  herein set forth  shall bind any party
hereto,  and no  one  of  them  has  relied  on  any  such  promise,  condition,


                                       14
<PAGE>

representation or warranty. Each of the parties hereto acknowledges that, except
as in this Amendment  Agreement  otherwise expressly stated, no representations,
warranties or commitments, express or implied, have been made by any other party
to the other. None of the terms or conditions of this Amendment Agreement may be
changed,  modified,  waived or canceled orally or otherwise,  except by writing,
signed by all the parties hereto, specifying such change,  modification,  waiver
or cancellation of such terms or conditions,  or of any proceeding or succeeding
breach thereof.

      11.  Ratification.  Except as hereby  specifically  amended,  modified  or
supplemented,  the  Agreement  and all of the other  Loan  Documents  are hereby
confirmed and ratified in all respects and shall remain in full force and effect
according to their respective terms.

      12. Consent of the Subsidiary Guarantors. Each Subsidiary Guarantor hereby
consents,  acknowledges and agrees to the amendments set forth herein and hereby
confirms,  reaffirms  and ratifies in all respects  the  Subsidiary  Guaranty to
which such Subsidiary  Guarantor is a party  (including  without  limitation the
continuation of such Subsidiary Guarantor's payment and performance  obligations
thereunder upon and after the effectiveness of this Agreement and the amendments
contemplated  hereby) and the enforceability of the Subsidiary  Guaranty against
such Subsidiary Guarantor in accordance with its terms.

      13.  Term  Loan  B.  Notwithstanding  anything  contained  in  the  Credit
Agreement or any other Credit Documents to the contrary,  after giving effect to
this Amendment  Agreement,  all references  contained in the Credit Agreement or
any  other  Credit  Document  to any "Term  Loan B  Lender",  the  "Term  Loan B
Facility",  "Term Loan B Outstandings" or any other reference to the Term Loan B
shall be null and void.


                                       15
<PAGE>

      IN  WITNESS  WHEREOF,  the  parties  hereto  have  caused  this  Amendment
Agreement to be duly executed by their duly authorized  officers,  all as of the
day and year first above written.

                                    BORROWER:

                                    RADIATION THERAPY SERVICES, INC.

                                    By: /s/ David M. Koeninger
                                        -----------------------------
                                    Name:David M. Koeninger
                                    Title: Executive Vice President

                                    GUARANTORS:

                                    21ST CENTURY ONCOLOGY, INC.

                                    21ST CENTURY ONCOLOGY OF NEW JERSEY, INC.

                                    21ST CENTURY ONCOLOGY OF KENTUCKY, LLC

                                    21ST CENTURY ONCOLOGY OF ALABAMA, INC.

                                    NEW YORK RADIATION THERAPY

                                    MANAGEMENT SERVICES, INC.

                                    NEVADA RADIATION THERAPY

                                    MANAGEMENT SERVICES, INC.

                                    FINANCIAL SERVICES OF SOUTHWEST

                                    FLORIDA, INC.

                                    RADIATION THERAPY SCHOOL FOR

                                    RADIATION THERAPY TECHNOLOGY, INC.

                                    MARYLAND RADIATION THERAPY

                                    MANAGEMENT SERVICES, INC.

                                    NORTH CAROLINA RADIATION THERAPY

                                    MANAGEMENT SERVICES, INC.

                                    CALIFORNIA RADIATION THERAPY

                                    MANAGEMENT SERVICES, INC.

                                    By: /s/ David M. Koeninger
                                        ----------------------
                                    Name: David M. Koeninger
                                    Title: Vice President


                                       16
<PAGE>

                                    BANK OF AMERICA, N.A., as Administrative
                                    Agent

                                    By: /s/
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    BANK OF AMERICA, N.A., as a Lender

                                    By: /s/
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    FIFTH THIRD BANK

                                    By: /s/
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    SUNTRUST BANK

                                    By: /s/
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    WACHOVIA BANK, NATIONAL ASSOCIATION

                                    By: /s/
                                        ----------------------------------------
                                    Name:
                                    Title:


                                       17
<PAGE>

                                    REGIONS BANK

                                    By: /s/
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    NATIONAL CITY BANK OF KENTUCKY

                                    By: /s/
                                        ----------------------------------------
                                    Name:
                                    Title:


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