Molecular characterization of chromosomal aberrations in non-Hodgkin's lymphoma (NHL) has provided a basic understanding of mechanisms of oncogene deregulation. Cytogenetic aberrations have been correlated with histologic subtype, immunophenotype, and clinical features of NHL. Although the incomplete specificity of some of the observed associations may limit the routine use of these markers in a clinical setting, the utilization of cytogenetic analysis can contribute to the diagnosis and management of patients with NHL.