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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.

Dated: May 7, 2007

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