This paper describes in non technical terms a new model, recently developed by the authors, which generalizes in several ways the traditional health care facility location models (Clarke,Wilson,1983; Mayhew,Taket,1980; Tadei, Gallino, Salomone, 1983; Wilson, Clarke, 1982). First, a multi-specialty structure is explicitly introduced,so that bundles of specialties, rather than aggregate hospital beds,are allocated over space. Secondly, patients are introduced in terms of their patient history, that is, each patient is associated with a sequence of stays in and transitions among different specialties and locations. This introduces interactions among all specialties and locations. Third, the evaluation and choice process associated with each patient history is treated as a stochastic multistage decision process, based on nested random utility theory (Bertuglia, Leonardi, Tadei, 1983; De Palma, Ben-Akiva, 1981; Domencich, McFadden, 1975; Leonardi, 1983; Leonardi, Campisi, 1981; Leonardi, Tadei, 1981; McFadden, 1978).