Common interface to different TTS engines * Handling concurrent synthesis requests =E2=80=93 requests may come asynchronously from multiple sources within an application and/or from more different applications. * Subsequent serialization, resolution of conflicts and priorities of incoming requests * Context switching =E2=80=93 state is maintained for each client connection independently, event for connections from within one application. * High-level client interfaces for popular programming languages * Common sound output handling =E2=80=93 audio playback is handled by Speech Dispatcher rather than the TTS engine, since most engines have limited sound output capabilities.