Sequential staining with Giemsa and quinacrine mustard on direct cytogenetic preparations was employed to characterize the karyotype of five bladder tumors of different stage and grade (TNM classification). The use of QFQ-banding allowed: the characterization of 2 euploid and 1 pseudodiploid cases, and the identification, in the two hyperdiploid cases, of a number of rearranged chromosomes otherwise morphologically indistinguishable from the normal ones. The importance of banding technique on direct cytogenetic preparations is stressed.