Released in 1998, SAMI (Synchronized Accessible Media Interchange) is a Microsoft accessibility initiative. The structured markup language is designed to simplify creating captions for media playback on a PC, i.e. Not for broadcast purposes.

SAMI documents are text, and can be written in any text editor, although there are special utilities available to create SAMI documents. They use .smi or .sami file extensions. The common use of .smi for SAMI files creates a file extension collision with SMIL files.

Each SAMI document may contain more than one language.