We will investigate the clinical manifestations and molecular genetic defects of heritable urologic malignant disorders. Families with urologic malignancy with known or suspected genetic basis will be enrolled. Affected individuals or individuals suspected of having a germline urologic malignant disorder will undergo periodic clinical assessment and genetic analyses for the purpose of: 1) definition and characterization of phenotype, 2) determination of the natural history of the disorder, and 3) genotype/phenotype correlation. Genetic linkage studies may be performed in situations in which the genetic basis of the disorder has not been elucidated.