This application proposes participation in the NIIMH cooperative agreement to establish Diagnostic Centers for Psychiatric Linkage Studies. In particular, it proposes participation in family studies of schizophrenia. Specifically, 66 families in which at least two sibs are diagnosed as schizophrenic according to DSM-IIIR criteria will be studied during years 2-4 of the proposed five year award. This application has several special strengths. It would be complemented and sponsored by an NIMH Clinical Research Center in psychiatric genetics. The principal investigators have extensive experience in the diagnosis and inheritance of schizophrenia, as well as the design and execution of linkage studies. The expertise of the investigators in psychiatric genetics in general, and schizophrenia in particular, would be useful to the proposed cooperative agreement between NIMH and several extramural sites.