Many monitoring programmes are successful at monitoring common species, whereas rare species, which are often of highest conservation concern, may be detected infrequently. Study designs that increase the probability of detecting rare species at least once over the study period, while collecting adequate data on common species, strengthen programme ability to address community-wide hypotheses about how an ecosystem functions or responds to management actions. Study design guidelines exist for single-species occupancy models, but practical guidance for monitoring species communities is needed. Single-species population-level designs are necessarily optimal for targeted species, whereas community study designs may be optimal for the assemblage of species, but not for every species within the community. Our objective was to provide a general optimization tool for multi-species models and to illustrate this tool using data from two avian community studies.