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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)) for the registrant
      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:  August 4, 2005                             /s/ David M. Dill
                                                  -----------------------------
                                                  David M. Dill
                                                  Executive Vice President and
                                                  Chief Financial Officer