Thoracic lymphomas, which are very common especially in Hodgkin's disease patients, are characterised by enlargement of mediastinal lymph nodes, parenchymal abnormalities, and pleural, pericardial and chest wall involvement. The use of several imaging techniques has been proposed in order to assess the extent of the disease correctly and to plan therapy. The most relevant results in this field, especially those using computed tomography (CT), magnetic resonance imaging (MRI) and gallium scanning, are summarised in this review. Presently CT is widely and successfully used in staging patients, whereas MRI seems to be preferable, as a second-step technique, if pericardial, pleural and chest wall involvement are suspected. The role of gallium scanning is limited in the staging, although it could be relevant in the follow-up of treated patients.