The HLA (Human Leucocyte Antigen) types and B were studied in 80 patients diagnosed as schizophrenic. There was an increased incidence of HLA-BW5 and a decrease in HLA-AW29 and HLA-BW17 as compared with healthy controls. In the sub-group of patients exhibiting Schneider's first-rank symptoms there was an increased incidence of HLA-A1 with a decrease in HLA-A2 and HLA-BW17.