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                                                                    Exhibit 31.2

               CERTIFICATION PURSUANT TO RULE 13a-14(a)/15d-14(a),
                             AS ADOPTED PURSUANT TO
                  SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, David M. Dill, certify that:

1.    I have reviewed this quarterly report on Form 10-Q of Renal Care Group,
      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(s) 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(s) 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: May 4, 2005                                 /s/ David M. Dill
                                                  -----------------------------
                                                  David M. Dill
                                                  Executive Vice President and
                                                  Chief Financial Officer