A research strategy which integrates known biological aspects of schizophrenia is proposed. The strategy includes genotype and phenotype components and emphasizes interactions. Its central feature is the comprehensive diagnostic assessment of patients with schizophrenia. Clinical and laboratory based methodologies are applied within the genotype and phenotype components of the strategy. Examples of research from each area and the potential interactions with other aspects of the strategy are presented. The expectation is that a greater understanding of the pathophysiology of schizophrenia will result from the application of the genotype-phenotype strategy and that consequently more efficacious treatments will ultimately be developed.