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                                                                  EXHIBIT 10 B1

                  CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER

                                 CERTIFICATIONS

I, Ronald E. Robison, certify that:

          1.   I have reviewed this report on Form N-CSR of Morgan Stanley
Allocator Fund,

          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, changes in net assets, and cash flows (if the
               financial statements are required to include a statement of cash
               flows) of the registrant as of, and for, the periods presented in
               this report;

          4.   The registrant's other certifying officers and I are responsible
               for establishing and maintaining disclosure controls and
               procedures (as defined in Rule 30a-2(c) under the Investment
               Company Act of 1940) for the registrant and have:

          a)   designed such disclosure controls and procedures 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)   evaluated the effectiveness of the registrant's disclosure
               controls and procedures as of a date within 90 days prior to the
               filing date of this report (the "Evaluation Date"); and

          c)   presented in this report our conclusions about the effectiveness
               of the disclosure controls and procedures based on our evaluation
               as of the Evaluation Date;

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          5.   The registrant's other certifying officers and I have disclosed,
               based on our most recent evaluation, to the registrant's auditors
               and the audit committee of the registrant's board of directors
               (or persons performing the equivalent functions):

          a)   all significant deficiencies in the design or operation of
               internal controls which could adversely affect the registrant's
               ability to record, process, summarize, and report financial data
               and have identified for the registrant's auditors any material
               weaknesses in internal controls; and

          b)   any fraud, whether or not material, that involves management or
               other employees who have a significant role in the registrant's
               internal controls; and

          6.   The registrant's other certifying officers and I have indicated
               in this report whether or not there were significant changes in
               internal controls or in other factors that could significantly
               affect internal controls subsequent to the date of our most
               recent evaluation, including any corrective actions with regard
               to significant deficiencies and material weaknesses.

          Date: September 22, 2003


                                          Ronald E. Robison

                                          Principal Executive Officer

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                                                                   EXHIBIT 10 B2

                  CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER

                                 CERTIFICATIONS

I, Francis Smith, certify that:

          1.   I have reviewed this report on Form N-CSR of Morgan Stanley
               Allocator Fund;

          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, changes in net assets, and cash flows (if the
               financial statements are required to include a statement of cash
               flows) of the registrant as of, and for, the periods presented in
               this report;

          4.   The registrant's other certifying officers and I are responsible
               for establishing and maintaining disclosure controls and
               procedures (as defined in Rule 30a-2(c) under the Investment
               Company Act of 1940) for the registrant and have:

          (i)  designed such disclosure controls and procedures 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;

          (ii) evaluated the effectiveness of the registrant's disclosure
               controls and procedures as of a date within 90 days prior to the
               filing date of this report (the "Evaluation Date"); and

          (iii) presented in this report our conclusions about the effectiveness
               of the disclosure controls and procedures based on our evaluation
               as of the Evaluation Date;

          5.   The registrant's other certifying officers and I have disclosed,
               based on our most recent evaluation, to the registrant's auditors
               and the audit committee of the registrant's board of directors
               (or persons performing the equivalent functions):

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          a)   all significant deficiencies in the design or operation of
               internal controls which could adversely affect the registrant's
               ability to record, process, summarize, and report financial data
               and have identified for the registrant's auditors any material
               weaknesses in internal controls; and

          b)   any fraud, whether or not material, that involves management or
               other employees who have a significant role in the registrant's
               internal controls; and

          6.   The registrant's other certifying officers and I have indicated
               in this report whether or not there were significant changes in
               internal controls or in other factors that could significantly
               affect internal controls subsequent to the date of our most
               recent evaluation, including any corrective actions with regard
               to significant deficiencies and material weaknesses.

          Date: September 22, 2003


                                          Francis Smith

                                          Principal Financial Officer