The Physical Computing Ensemble was created in order to determine the viability of an approach to musical performance which focuses on the relationships and interactions of the performers. Three performance systems utilizing gestural controllers were designed and implemented, each with a different strategy for performer interaction. These strategies took advantage of the opportunities for collaborative performance inherent in digital musical instruments due to their networking abilities and reconfigurable software. These characteristics allow for the easy implementation of varying approaches to collaborative performance. Ensembles who utilize digital musical instruments provide a fertile environment for the design, testing, and utilization of collaborative performance systems. The three strategies discussed in this paper are the parameterization of musical elements, turn-based collaborative control of sound, and the interaction of musical systems created by multiple performers. Design principles, implementation, and a performance using these strategies are discussed, and the conclusion is drawn that performer interaction and collaboration as a primary focus for system design, composition, and performance is viable.