Abstract: This paper presents a paradigm for automatically generating complete camera specifications for capturing events in virtual 3D environments in real-time. We describe a fully implemented system, called the Virtual Cinematographer, and demonstrate its application in a virtual "party" setting. Cinematographic expertise, in the form of film idioms, is encoded as a set of small hierarchically organized finite state machines. Each idiom is responsible for capturing a particular type of scene, such as three virtual actors conversing or one actor moving across the environment. The idiom selects shot types and the timing of transitions between shots to best communicate events as they unfold. A set of camera modules, shared by the idioms, is responsible for the low-level geometric placement of specific cameras for each shot. The camera modules are also responsible for making subtle changes in the virtual actors' positions to best frame each shot. In this paper, we discuss some basic heuristics of filmmaking and show how these ideas are encoded in the Virtual Cinematographer.