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                                                                 EXHIBIT 31(a)

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

I, Jeffry N. Quinn, certify that:

1. I have reviewed this Quarterly Report on Form 10-Q of Solutia 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 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 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 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 3, 2007

                                            /s/  Jeffry N. Quinn
                                         ----------------------------------
                                                    Jeffry N. Quinn
                                         President, Chief Executive Officer and
                                                 Chairman of the Board