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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.
                                        May 11, 2007