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                                                              Exhibit 99.906CERT

                            SECTION 906 CERTIFICATION

                Certification Pursuant to 18 U.S.C. Section 1350,
                             As Adopted Pursuant to
                  Section 906 of the Sarbanes-Oxley Act of 2002

Morgan Stanley KLD Social Index Fund

       In connection with the Report on Form N-CSR (the "Report") of the
above-named issuer for the period ended May 31, 2004 that is accompanied by this
certification, the undersigned hereby certifies that:

1.     The Report fully complies with the requirements of Section 13(a) or 15(d)
       of the Securities Exchange Act of 1934; and

2.     The information contained in the Report fairly presents, in all material
       respects, the financial condition and results of operations of the
       Issuer.


Date: July 20, 2004                             /s/ Ronald E. Robison
                                                ---------------------
                                                Ronald E. Robison
                                                Principal Executive Officer


A signed original of this written statement required by Section 906 has been
provided to Morgan Stanley KLD Social Index Fund and will be retained by Morgan
Stanley KLD Social Index Fund and furnished to the Securities and Exchange
Commission or its staff upon request.

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                            SECTION 906 CERTIFICATION

                Certification Pursuant to 18 U.S.C. Section 1350,
                             As Adopted Pursuant to
                  Section 906 of the Sarbanes-Oxley Act of 2002

Morgan Stanley KLD Social Index Fund

       In connection with the Report on Form N-CSR (the "Report") of the
above-named issuer for the period ended May 31, 2004 that is accompanied by this
certification, the undersigned hereby certifies that:

1.     The Report fully complies with the requirements of Section 13(a) or 15(d)
       of the Securities Exchange Act of 1934; and

2.     The information contained in the Report fairly presents, in all material
       respects, the financial condition and results of operations of the
       Issuer.


Date: July 20, 2004                             /s/ Francis Smith
                                                -----------------
                                                Francis Smith
                                                Principal Financial Officer


A signed original of this written statement required by Section 906 has been
provided to Morgan Stanley KLD Social Index Fund and will be retained by Morgan
Stanley KLD Social Index Fund and furnished to the Securities and Exchange
Commission or its staff upon request.