DEVELOPMENT AGREEMENT

Exhibit 10.46

DEVELOPMENT AGREEMENT

THIS DEVELOPMENT AGREEMENT (this “ Agreement ”) is made and entered into as of this 10 ^th day of February, 2005 to be effective as of December 16, 2004 (the “ Effective Date ”) by and between Palm Springs Radiation Enterprises, LLC , a California limited liability company (“ Owner ”) and California Radiation Therapy Management Services, Inc. , a California corporation (“ Management Services ”).

RECITALS:

A. Owner is the owner of all that certain real property located in the City of Palm Desert, Riverside County (“ County ”), State of California, having a street address of 77-840 Flora Road, Palm Desert, California, and more particularly described on Exhibit “A” attached hereto and made a part hereof (the “ Property ”).

B. Management Services is a wholly owned subsidiary of Radiation Therapy Services, Inc., a Florida corporation (“ RTSI ”), a developer and operator of radiation therapy centers.

C. Owner and Management Services have previously agreed that Owner shall develop the Property as a radiation therapy center meeting the standards and requirements of RTSI for a radiation therapy center under its 21 ^st Century Oncology flagship brand (the “ Project ”) and shall deliver the same to Management Services on a turnkey basis for operation and/or leasing by Management Services.

D. The parties are mutually desirous of entering into this Agreement in order set forth their understanding relative to the development and delivery to Management Services of the Project.

NOW THEREFORE, in consideration of the foregoing and for other valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties agree as follows:

SECTION 1

PROJECT DESIGN

1.1 Project Architect . The parties agree to the appointment of Architectronix, Inc., a California Professional Corporation as the “ Project Architect ”. The scope of services and total fees and costs for each stage thereof is set forth in those certain agreements for architectural services executed by and between Owner and Project Architect dated July 23, 2003 and December 7, 2004 (the “ Architectural Agreement ”), copies of which are attached hereto as Exhibit “B”.

1.2 Previously Prepared Plans and Specifications . The Project Architect has prepared certain plans and specifications for the Project, a detailed listing of which is set forth on Exhibit “C” attached hereto and made a part hereof (the “ Plans ”), which Plans are sufficient to fully complete the Project on a “turnkey” basis for delivery to Management Services as herein contemplated and which existing Plans are acceptable to the parties.

1.3 Additional Plans and Specifications to be Agreed Upon . To the extent that the Plans do not provide all necessary elements for the full completion of the Project as herein contemplated or in the event that additional plans are necessary for the completion of the Project, additional plans and specifications for the balance of the Project will be agreed upon by the parties in accordance with Section 2 of this Agreement.

SECTION 2

PLANS

2.1 Subsequent Plan Approval . Upon execution of this Agreement, the parties shall have each approved the Plans as set forth on Exhibit “C”. To the extent Additional Plans are necessary as herein provided, Management Services shall approve the Additional Plans within fifteen (15) Business Days following receipt thereof from Owner. The failure of Management Services to disapprove such Additional Plans within such Fifteen (15) Business Day period shall constitute its approval thereof. If Management Services reasonably disapproves the Additional Plans, then Management Services shall notify Owner in writing of any reasonably required changes, and Owner shall promptly incorporate any such changes into the Plans and redeliver them, as revised, to Management Services for approval. In any case, the Plans and any Additional Plans shall comply with all laws, rules, and regulations of all governmental authorities having jurisdiction over the Property, as well as the requirements of any such governmental authorities which must accept any elements of the Project to be constructed pursuant to the terms hereof (herein, “ Governmental Requirements ”) and in accordance with all standards of RTSI relative to 21 ^st Century Oncology Centers.

2.2 Resolution of Disputes . Any dispute with respect to the Plans or any Additional Plans shall be resolved by the submission of such issue to an independent California licensed architect jointly selected by the parties, which independent architect shall have at least ten (10) years’ experience in the construction of improvements similar to the Project and who shall not have worked for either of the parties within three (3) years prior to the date of this Agreement. If the parties cannot agree on the selection of an independent architect, then Management Services shall select the same. Such selection and the decision rendered by such selected independent architect shall in all events be accomplished within fifteen (15) Business Days after the date either party notifies the other of the dispute, and shall be binding upon the parties. The fees of the independent architect engaged to resolve a dispute between the parties relative to the Plans shall be split equally by the parties involved in the dispute.

2.3 Additional Plans and Specifications . Additional Plans approved pursuant to the terms of this Section shall be deemed to be included within the definition of Plans once approved.

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SECTION 3

DEVELOPMENT OF PROJECT

3.1 Development . Owner shall be solely and exclusively responsible, subject to all approval rights of Management Services hereunder, at its sole cost and expense to commence, diligently prosecute and complete the Project in accordance with the Plans, all Governmental Requirements and standards required by RTSI so as to deliver to Management Services on a “turnkey” basis upon completion a first class radiation therapy center and facility. Owner shall be solely responsible for obtaining, at its sole cost and expense, any and all governmental permits, licenses and approvals necessary for the construction, completion and equipping of the Project. Owner hereby represents and warrants to Management Services that all required permits and approvals necessary for the construction, completion and equipping of the Project.

3.2 Financing . Owner acknowledges, covenants and agrees that it is solely responsible for investment of all equity investment in to the Project, as well as for obtaining financing for the construction, completion and equipping of the Project. Owner represents and warrants and covenants and agrees with Management Services that it shall obtain all financing for the construction and completion of the Project and shall disclose to Management Services the name of any institutional lender providing such financing and the terms thereof. Owner agrees that it shall provide to Management Services within ten (10) days from entering into any such financing, true, complete and correct copies of all loan documents evidencing and/or securing said financing.

3.3 Contract and Contractor . Management Services has previously entered into a Standard Form of Agreement Between Owner and Contractor (AIA Document A101—1997) (the “ General Contract ”) with ACN Construction, Inc. (“ Contractor ”) for construction and completion of the Project, a true, correct and complete copy of which is attached hereto as Exhibit “D”. Contemporaneously with the execution and delivery hereof, Management Services and Owner shall enter into an Assignment of Construction Contract pursuant to which Management Services shall assign to Owner the General Contract and all of Management Services’ rights thereunder, and Owner shall assume and agree to perform and indemnify Management Services from all obligations, liabilities and performances required to be performed by Management Services under the General Contract. The General Contract is an unclassified, fixed price contract, providing for progress payments, retainage of not less than ten percent (10%) of each such progress payment, and with final payment to be conditioned upon the parties’ approval of the Project (which approval shall not be unreasonably withheld or delayed), and certification by the Project Architect that the Project has been completed in accordance with the Plans.

3.4 Completion of Project . Owner shall cause the Contractor to substantially complete the Project in accordance with the construction schedule set forth on Schedule 1 hereto (the “ Construction Schedule ”), including without limitation the Completion Date

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provided therein, subject only to Punch List items (defined below), and in accordance with the construction budget set forth on Schedule 2 hereto (the “ Project Budget ”). The Project shall be performed in a good and workmanlike manner using sound construction practices and so as to comply with the Plans, all Governmental Requirements and all standards established by RTSI for a radiation therapy center. Upon substantial completion of the Project and issuance of a Certificate of Occupancy therefor, Owner shall cause the Project Architect to provide a written certification to Management Services that all work for the Project has been completed in accordance with the Plans. Within fifteen (15) days following substantial completion of the Project and issuance of a Certificate of Occupancy therefor, Owner and Management Services shall meet and confer to prepare a written punch list setting forth any incomplete or defective items of the Project that require additional work by Owner (“ Punch List ”). To the extent reasonably practicable, Owner shall perform or cause all items of work disclosed in the Punch List to be fully performed and completed within thirty (30) days following completion of the Punch List, provided that if such work requires more than thirty (30) days to complete, Owner shall not be in default hereunder if it commences to cure such Punch List items within such thirty (30) day period and diligently pursues such cure to completion.

3.5 Equipping of Project . Owner acknowledges and agrees that Devoto Construction of Southwest Florida, Inc. (“ Devoto ”), an affiliate of RTSI, shall serve as purchasing manager of certain of the equipment and other items required to complete the equipping of the Project in accordance with the Plans and the standards and requirements of RTSI. Owner acknowledges that Devoto is able to achieve certain savings relative to the purchase of such equipment as a result of its relationship with vendors providing the same. Owner agrees that contemporaneously with the execution and delivery hereof, it shall enter into a Purchasing Agreement with Devoto in the form attached hereto as Exhibit “E”, to manage and arrange the purchase and installation of such equipment.

3.6 Change Orders . Any change order and corresponding revisions to the Project or the Plans requested shall be subject to the prior written approval of Owner, with major or material change orders also subject to the prior approval of Management Services.

3.5 Indemnification . Owner shall and does hereby indemnify Management Services and RTSI, and their general and limited partners, officers, directors, members, managers, employees, agents, shareholders, successors and assigns (collectively, the “ Indemnified Parties ”), and holds the Indemnified Parties harmless from all loss, damage, cost, expense and attorneys’ fees that any of the Indemnified Parties may suffer at any time by reason of or arising as a result of the activities performed by Owner, it’s agent, employees and/or contractor(s) under this Agreement, including without limitation the construction and completion of the Project. Owner hereby agrees to cause Management Services and RTSI to be named as additional insureds under any and all liability and builder’s risk insurance policies issued in connection with the Project.

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SECTION 4

COMPLETION OF PROJECT

4.1 Operating Agreement; Lease . Upon completion of the Project as evidenced by the delivery of a Certificate of Occupancy therefor and provided that the Project has been fully equipped and otherwise accepted by Management Services, Owner and Management Services shall enter into an Operating Agreement and/or Lease pursuant to which Management Services shall manage and operate the completed Project generally upon the business terms set forth on Exhibit “F” attached hereto and made a part hereof.

SECTION 5

DEFAULT; SELF HELP

5.1 Owner Default . Owner shall be deemed in default of this Agreement if it fails to provide due diligence to Management Services to insure performance pursuant to the Construction Contract.

SECTION 6

GENERAL PROVISIONS

6.1 Termination . Unless sooner terminated for default or otherwise, this Agreement shall terminate upon satisfaction of all the following conditions: (i) Owner’s full completion of the Project; (ii) Management Services’ acceptance of the completed Project; and (iii) Management Services’ and Owner’s entry into an operating agreement or lease relative to the operation of the completed Project.

6.2 Binding Effect . Subject to any provision hereof restricting assignment, this Agreement shall be binding upon and inure to the benefit of the executing parties and their respective successors and assigns.

6.3 Costs and Attorneys’ Fees . If any party to this Agreement brings or commences any legal action or proceeding to enforce any of the terms of this Agreement (or for damages by reason of an alleged breach of this Agreement), the prevailing party in such action shall be entitled to recovery of all costs and expenses of litigation, including reasonable attorneys’ fees and costs, as part of its judgment. The prevailing party shall also be entitled to recovery of all costs and expenses, including reasonable attorneys’ fees, in enforcing any judgment awarded to it.

6.4 Relationship of Parties . Nothing contained in this Agreement shall be deemed or construed, either by the parties hereto or by any third party, to create the relationship of principal and agent or create any partnership, joint venture or other association between Owner and Management Services.

6.5 Notices . All notices, including deliveries of documentation ( i.e. , plans and contracts) for review and approval herein shall be sent by either personal delivery, a

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reputable overnight courier which keeps receipts of delivery (such as UPS or Federal Express), or through the facilities of the United States Post Office, postage prepaid, certified or registered mail, return receipt requested. Any such notice shall be effective upon delivery, if delivered by personal delivery or overnight courier, and seventy-two (72) hours after dispatch, if mailed in accordance with the above. Notices to the respective parties shall be sent to the following addresses unless written notice of a change of address has been previously given pursuant hereto:

6.6 Consents . Whenever in this Agreement a party is, or may be, called upon to give its consent or approval to any action, except as otherwise specifically provided herein, the consent or approval shall not be unreasonably withheld or delayed.

6.7 Exhibits Incorporated . Each exhibit and schedule attached hereto and referred to in this Agreement is hereby incorporated by reference as though set forth in full where referred to (by letter or description) herein.

6.8 Force Majeure . If Owner is delayed in the performance of the Project for more than 90 days by reason of force majeure such as fire, earthquake, hurricane or war, riots, strikes, lockouts, insurrections, unusually severe, adverse weather conditions, or any other condition beyond Owner’s reasonable control, then the Construction Schedule shall be extended by the appropriate number of days to account for such delay.

6.9 Entire Agreement; Modification . This Agreement (including the Recitals set forth at the beginning of this Agreement, all of which are incorporated herein by this reference) embodies and constitutes the entire understanding between the parties with respect to the transaction contemplated herein. All prior or contemporaneous agreements, understandings, representations and statements, oral or written, are merged into this Agreement. Neither this Agreement nor any provision hereof may be waived, modified, discharged, or terminated except by an instrument in writing signed by the party against which the enforcement of such waiver, modification, amendment, discharge or termination is sought, and then only to the extent set forth in such instrument.

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7.12 Applicable Law . This Agreement shall be governed by, and construed in accordance with, the laws of Florida.

7.13 Headings . Descriptive headings are for convenience only and shall not control or affect the meaning or construction of any provision of this Agreement.

7.14 Interpretation . Whenever the context hereof shall so require, the singular shall include the plural, the male gender shall include the female gender and the neuter, and vice versa, and the use of the terms “include,” “includes” and “including” shall be without limitation to the items which follow.

7.15 Severability . In case any one or more of the provisions hereof shall for any reason be held to be invalid, illegal or unenforceable in any respect, such invalidity, illegality or unenforceability shall not affect any other provision hereof, and this Agreement shall be construed as if such invalid, illegal or unenforceable provision had never been contained herein.

7.16 Joint Drafting . The parties acknowledge that each has played an equal part in the negotiation and drafting of this Agreement, and in the event any ambiguities should be realized in the construction or interpretation of this Agreement, such ambiguities shall not be construed against either party solely on account of authorship.

7.17 Time is of the Essence . The parties acknowledge that time is of the essence for each time and date specifically set forth in this Agreement.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement on the day and year first written above.

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Exhibit “A”

Legal Description

LEGAL DESCRIPTION

The land referred to herein is situated in the State of California, County of RIVERSIDE, Unincorporated Area, described as follows:

PARCEL 36 OF PARCEL MAP NO. 29715-1, AS FILED IN BOOK 202 AT PAGES 35 THROUGH 39, INCLUSIVE, OF PARCEL MAPS, RECORDS OF RIVERSIDE COUNTY, CALIFORNIA, TOGETHER WITH PARCEL “A” OF CERTIFICATE OF PARCEL MERGER NO. 01354, RECORDED JULY 1, 2003, AS INSTRUMENT NO. 2003-487225, RECORDS OF RIVERSIDE COUNTY, CALIFORNIA, DESCRIBED AS FOLLOWS:

BEGINNING AT THE NORTHWEST CORNER OF SAID PARCEL A; THENCE ALONG THE NORTH LINE OF SAID PARCELS “A” AND 36, SOUTH 89 16’55” EAST, 396.41 FEET TO THE NORTHEAST CORNER OF PARCEL 36; THENCE ALONG THE EAST LINE OF SAID PARCEL 36 THE FOLLOWING TWO COURSES: SOUTH 00 43’05” WEST 102.12 FEET; THENCE SOUTH 42 55’16” EAST 123.44 FEET TO THE SOUTH LINE OF PARCEL 36 AND THE BEGINNING OF A NON-TANGENT CURVE CONCAVE SOUTHEASTERLY AND HAVING A RADIUS OF 628.50 FEET, A RADIAL LINE THROUGH SAID POINT BEARS NORTH 1 52’15” WEST; THENCE ALONG SAID CURVE AND SOUTH LINE THROUGH A CENTRAL ANGLE OF 31 16’00” AN ARC LENGTH OF 342.98 FEET TO THE BEGINNING OF A REVERSE CURVE CONCAVE NORTHERLY AND HAVING A RADIUS OF 24.50 FEET, A RADIAL LINE THROUGH SAID POINT BEARS NORTH 33 08’15” WEST; THENCE WESTERLY AND NORTHWESTERLY ALONG SAID CURVE THROUGH A CENTRAL ANGLE OF 82 54’07” AN ARC LENGTH OF 35.45 FEET TO THE BEGINNING OF A REVERSE CURVE CONCAVE SOUTHWESTERLY AND HAVING A RADIUS OF 228.50 FEET, A RADIAL LINE THROUGH SAID POINT BEARS NORTH 49 45’52” EAST; THENCE NORTHWESTERLY ALONG SAID CURVE THROUGH A CENTRAL ANGLE OF 37 42’44” AN ARC LENGTH OF 150.40 FEET TO THE SOUTHWEST CORNER OF SAID PARCEL “A” A RADIAL LINE THROUGH SAID POINT BEARS NORTH 12 03’08” EAST; THENCE ALONG THE WEST LINE OF PARCEL “A”, NORTH 00 42’34” EAST 218.83 FEET TO THE NORTHWEST CORNER OF PARCEL “A” AND POINT OF BEGINNING.

NOTE: SAID LAND IS DESCRIBED AND DELINEATED AS PARCEL 21-B IN THAT CERTAIN CERTIFICATE OF PARCEL MERGER NO. 1401 RECORDED AUGUST 28, 2003 AS INSTRUMENT NO. 2003-665897 OF OFFICIAL RECORDS.

End of Legal Description

Exhibit “B”

Architectural Agreement