There is a long history of describing communities in ecology. It is now time to develop a general predictive framework for this discipline. The goal is to simultaneously provide a consistent theoretical framework to guide research and a practical framework to guide conservation of wild landscapes. We propose that this framework has four key elements: the species pool vector P, the local community vector C, a vector of environmental filters E, and a vector of functional traits T. The central challenge of community ecology is to predict the species composition of any community C, using prior knowledge of P, E and T. Common filters include flooding, fire and herbivory. Each community C is a subset of the regional species pool P and is the result of filtering that matches species’ traits to the local environmental conditions. Dispersal, competition and time are also important in community assembly.