An electronic marketplace where National Association of Securities Dealer (NASD) members could execute trades, communicate, and receive quotations on stocks listed on the New York Stock Exchange (NYSE) and the American Stock Exchange (Amex). Formerly known as "Nasdaq's third market", Nasdaq Intermarket used Nasdaq's Computer Assisted Execution System (CAES) to connect buy and/or sell orders. Nasdaq announced its intentions to withdraw from the Intermarket Trading system in 2005.

Nasdaq Intermarket competed for retail stock orders with regional exchanges such as the Chicago Stock Exchange (CHX) and the Boston Stock Exchange (BSE). By connecting several stock exchanges, the intermarket system gave traders access to additional buyers and/or sellers, increasing liquidity and competition.