A streaming composition system is described herein that provides easy workflow and playback capabilities for content producers to create composite media assets from existing and on-going media content and for streaming clients to seamlessly playback composite multimedia streams provided from different sources. These assets provide broadcasters an option to quickly turn around highlights for an on-going event. The streaming composition system allows a producer to identify clips within existing media assets and compose the clips into a new unified streaming presentation. For producers that already have smooth streaming media assets, the system leverages these assets to provide seamless playback across clip boundaries including advanced playback support for advertisement insertion, fast forward, rewind, and so on.