The classification of both Hodgkin's and non-Hodgkin's lymphomas continues to evolve. The current World Health Organization classification incorporates data derived from advances in our understanding of the pathogenesis of these disorders together with their distinguishing immunophenotypic, genotypic, clinical and histopathological characteristics. As outcomes have improved, the main emphasis of treatment has been to incorporate a risk-adapted approach to reduce long-term toxicity without sacrificing efficacy through the use of varying combinations of chemotherapy, radiotherapy and immunotherapy.