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                                                                    EXHIBIT 31.2

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350
                             AS ADOPTED PURSUANT TO
                  SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Mark D. Stolper, certify that:

1. I have reviewed this report on Form 10-K of RadNet, Inc.

2. Based on my knowledge, this report does not contain any untrue statement of a
material fact or omit to state a material fact necessary to make the statements
made, in light of the circumstances under which such statements were made, not
misleading with respect to the period covered by this report.

3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the registrant as
of, and for, the periods presented in this report;

4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial
reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the
registrant and have:

      a.   designed such disclosure controls and procedures, or caused such
           disclosure controls and procedures to be designed under our
           supervision, to ensure that material information relating to the
           registrant, including its consolidated subsidiaries, is made known to
           us by others within those entities, particularly during the period in
           which this report is being prepared;

      b.   designed such internal control over financial reporting, or caused
           such internal control over financial reporting to be designed under
           our supervision, to provide reasonable assurance regarding the
           reliability of financial reporting and the preparation of financial
           statements for external purposes in accordance with generally
           accepted accounting principles;

      c.   evaluated the effectiveness of the registrant's disclosure controls
           and procedures and presented in this report our conclusions about the
           effectiveness of the disclosure controls and procedures, as of the
           end of the period covered by this report based on such evaluation;
           and

      d.   disclosed in this report any change in the registrant's internal
           control over financial reporting that occurred during the
           registrant's most recent fiscal quarter (the registrant's fourth
           fiscal quarter in the case of an annual report) that has materially
           affected, or is reasonably likely to materially affect, the
           registrant's internal control over financial reporting; and

5. The registrant's other certifying officer and I have disclosed, based on our
most recent evaluation of internal control over financial reporting, to the
registrant's auditors and the audit committee of the registrant's board of
directors (or persons performing the equivalent functions):

      a.   all significant deficiencies and material weaknesses in the design or
           operation of internal control over financial reporting which are
           reasonably likely to adversely affect the registrant's ability to
           record, process, summarize and report financial information; and

      b.   any fraud, whether or not material, that involves management or other
           employees who have a significant role in the registrant's internal
           control over financial reporting.

Dated:   March 16, 2009


                                                 /s/ Mark D. Stolper
                                                 -------------------------------
                                                     MARK D. STOLPER
                                                     EXECUTIVE VICE PRESIDENT
                                                     AND CHIEF FINANCIAL OFFICER