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                                                                    EXHIBIT 12.1

                     CERTIFICATION PURSUANT TO SECTION 302
                       OF THE SARBANES-OXLEY ACT OF 2002

     I, Ben J. Lipps, certify that:

     1.    I have reviewed this annual report on Form 20-F of Fresenius Medical
           Care Aktiengesellschaft (the "Report").

     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 company as of, and for, the periods presented in this
           Report.

     4.    The company's other certifying officer and I am responsible for
           establishing and maintaining disclosure controls and procedures (as
           defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
           company 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
              company, 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 company'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 company's internal
              control over financial reporting that occurred during the period
              covered by the annual report that has materially affected, or is
              reasonably likely to materially affect, the company's internal
              control over financial reporting.

     5.    The company's other certifying officer and I have disclosed, based on
           our most recent evaluation of internal control over financial
           reporting, to the company's auditors and the audit committee of the
           company'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 company'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 company's
              internal control over financial reporting.

Date: March 1, 2005

                                          /s/ DR. BEN J. LIPPS
                                        ----------------------------------------
                                          Dr. Ben J. Lipps
                                          Chief Executive Officer and
                                          Chairman of the Management Board