If you are a software developer wanting to incorporate speech recognition and voice output into your application, we have sample source code that can get you started. We have samples for the native Speech API (SAPI) and the managed System.Speech namespace (Recognition and Synthesis).
The samples are part of the Windows SDK and the most recent versions were included in the Windows SDK for Windows Server 2008 and Vista SP1.
The Windows SDK completely replaces the older SAPI 5.1 SDK and supports development on Windows XP, Windows Server 2003, Windows Vista, and Windows Server 2008.
To get the samples, customers can download this SDK as a DVD image (1,330MB ISO file), or go through a guided setup process where only the components they need are downloaded. Speech is part of the base install.