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                                                                  Exhibit 31.2

                     CHIEF FINANCIAL OFFICER CERTIFICATION

I, Steven Novik, certify that:

1.   I have reviewed this quarterly report on Form 10-Q of The Jones Financial
     Companies, L.L.L.P.

2.   Based on my knowledge, this quarterly 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 quarterly report.

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

4.   The Partnership'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
     Partnership 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
          Partnership, including its consolidated subsidiaries, is made known
          to us by others within those entities, particularly during the
          period in which this quarterly report is being prepared;

     b)   Evaluated the effectiveness of the Partnership's disclosure controls
          and procedures and presented in this quarterly 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 Partnership's internal
          control over financial reporting that occurred during the
          Partnership's most recent fiscal quarter that has materially
          affected, or is reasonably likely to materially affect, the
          Partnership's internal control over financial reporting; and

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

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

     b)   Any fraud, whether or not material, that involves management or
          other associates who have a significant role in the Partnership's
          internal control over financial reporting.

                                        /s/ Steven Novik
                                        ---------------------------------------
                                        Chief Financial Officer
                                        The Jones Financial Companies, L.L.L.P.
                                        August 8, 2007



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