A theory of the distributed detection of radar targets is developed. The radar system employs a number of physically separated peripheral receivers and detectors and a central processor that provides a final decision by combining peripheral decisions rather than decision statistics. Various combining strategies are studied in the context of overall system optimality. It is shown that the optimal decision strategy of a peripheral detector depends on the strategies of the other peripheral detectors and, interestingly, on the structure of the central processor. To illustrate application of the theory, the design of a distributed system in a Rayleigh fading environment is studied.