The role of radiotherapy in the treatment of Hodgkin's disease and non-Hodgkin's lymphoma has changed considerably in the last few decades. Clinical observation of mainly unicentric pathogenesis with continuous expansion and subclinical involvement of adjoining regions of lymph nodes has resulted in the introduction of a large-field technique with total nodal irradiation (TNI) or total lymphatic irradiation (TLI). The introduction of polychemotherapy has led to further improvement in the cure rate and in considerations concerning using both methods and adapting them to the stage and risk. Today the combination of radiation and chemotherapy leads to a reduction in the amount of radiation required in the affected regions (involved field irradiation = IFI).