Multimedia scheduling models provide a rich variety of tools for managing the synchronization of media like video and audio, but generally have an inflexible model for time itself. In contrast, modern animation models in the computer graphics community generally lack tools for synchronization and structural time, but allow for a flexible concept of time, including variable pacing, acceleration and deceleration and other tools useful for controlling and adapting animation behaviors. Multimedia authors have been forced to choose one set of features over the others, limiting the range of presentations they can create. Some programming models addressed some of these problems, but provided no declarative means for authors and authoring tools to leverage the functionality. This paper describes a new model incorporated into SMIL 2.0 that combines the strengths of scheduling models with the flexible time manipulations of animation models. The implications of this integration are discussed wit...