Sep. 30, 2019
Global Concentrated Portfolio
Global Concentrated Portfolio
Prospectus Supplement September 30, 2019 Morgan Stanley Institutional Fund, Inc. Supplement dated September 30, 2019 to the Morgan Stanley Institutional Fund, Inc. Prospectus dated April 30, 2019 Global Concentrated Portfolio
The following is hereby added as the fourth paragraph of the section of the Prospectus entitled "Fund Summary—Global Concentrated Portfolio—Principal Investment Strategies": The Adviser actively integrates sustainability analysis as a part of its bottom up stock selection component of the investment process. Sustainability analysis is inclusive of environmental; social and human capital; and business model, innovation, leadership and governance ("ESG") issues. The Adviser gives particular credence to those ESG issues deemed to be material to a given industry, shown to potentially impact a company's long term stock price performance. Please retain this supplement for future reference.

Risk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicated

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Principal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.

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