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                                                                    EXHIBIT 31.2

                                 SYMBION, INC.
                              ANNUAL CERTIFICATION
           PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Kenneth C. Mitchell, certify that:

      1. I have reviewed this annual report on Form 10-K of Symbion, 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)) 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) 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

        (c) 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;

      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.

Date: March 28, 2005

                                           /s/ Kenneth C. Mitchell
                                           -------------------------------------
                                           Kenneth C. Mitchell
                                           Chief Financial Officer and
                                           Senior Vice President of Finance