September 8, 2006

Supplement

SUPPLEMENT DATED SEPTEMBER 8, 2006 TO THE PROSPECTUS OF
MORGAN STANLEY VARIABLE INVESTMENT SERIES
THE HIGH YIELD PORTFOLIO
CLASS X and CLASS Y
Dated May 1, 2006 

The following disclosure is hereby added at the end of the section of the Portfolio’s Prospectus titled ‘‘Additional Investment Strategy Information — Forward Foreign Currency Exchange Contracts’’: 

The Portfolio may also enter into cross currency hedges, which involve the sale of one currency against the positive exposure to a different currency. Cross currency hedges may be used for hedging purposes or to establish an active exposure to the exchange rate between any two currencies. 

The following disclosure is hereby added at the end of the section of the Portfolio’s Prospectus titled ‘‘Additional Risk Information — Forward Foreign Currency Exchange Contracts’’: 

For cross currency hedges, there is an additional risk to the extent that these transactions create exposure to currencies in which the Portfolio’s securities are not denominated. 

PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE. 

LIT SPT VAR HI 09/06

September 8, 2006

Supplement

SUPPLEMENT DATED SEPTEMBER 8, 2006 TO THE PROSPECTUS OF
MORGAN STANLEY VARIABLE INVESTMENT SERIES
THE STRATEGIST PORTFOLIO
CLASS X and CLASS Y
Dated May 1, 2006 

The following disclosure is hereby added at the end of the section of the Portfolio’s Prospectus titled ‘‘Additional Investment Strategy Information — Forward Foreign Currency Exchange Contracts’’: 

The Portfolio may also enter into cross currency hedges, which involve the sale of one currency against the positive exposure to a different currency. Cross currency hedges may be used for hedging purposes or to establish an active exposure to the exchange rate between any two currencies. 

The following disclosure is hereby added at the end of the section of the Portfolio’s Prospectus titled ‘‘Additional Risk Information — Forward Foreign Currency Exchange Contracts’’: 

For cross currency hedges, there is an additional risk to the extent that these transactions create exposure to currencies in which the Portfolio’s securities are not denominated. 

PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE. 

LIT SPT VAR ST 09/06

September 8, 2006

Supplement

SUPPLEMENT DATED SEPTEMBER 8, 2006 TO THE PROSPECTUS OF
MORGAN STANLEY VARIABLE INVESTMENT SERIES
THE INCOME PLUS PORTFOLIO
CLASS X and CLASS Y
Dated May 1, 2006 

The following disclosure is hereby added at the end of the section of the Portfolio’s Prospectus titled ‘‘Additional Investment Strategy Information — Forward Foreign Currency Exchange Contracts’’: 

The Portfolio may also enter into cross currency hedges, which involve the sale of one currency against the positive exposure to a different currency. Cross currency hedges may be used for hedging purposes or to establish an active exposure to the exchange rate between any two currencies. 

The following disclosure is hereby added at the end of the section of the Portfolio’s Prospectus titled ‘‘Additional Risk Information — Forward Foreign Currency Exchange Contracts’’: 

For cross currency hedges, there is an additional risk to the extent that these transactions create exposure to currencies in which the Portfolio’s securities are not denominated. 

PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE. 

LIT SPT VAR IP 09/06

September 8, 2006

Supplement

SUPPLEMENT DATED SEPTEMBER 8, 2006 TO THE PROSPECTUS OF
MORGAN STANLEY VARIABLE INVESTMENT SERIES
THE LIMITED DURATION PORTFOLIO
CLASS X and CLASS Y
Dated May 1, 2006 

The following disclosure is hereby added at the end of the section of the Portfolio’s Prospectus titled ‘‘Additional Investment Strategy Information — Forward Foreign Currency Exchange Contracts’’: 

The Portfolio may also enter into cross currency hedges, which involve the sale of one currency against the positive exposure to a different currency. Cross currency hedges may be used for hedging purposes or to establish an active exposure to the exchange rate between any two currencies. 

The following disclosure is hereby added at the end of the section of the Portfolio’s Prospectus titled ‘‘Additional Risk Information — Forward Foreign Currency Exchange Contracts’’: 

For cross currency hedges, there is an additional risk to the extent that these transactions create exposure to currencies in which the Portfolio’s securities are not denominated. 

PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE. 

LIT SPT VAR LD 09/06