Ten patients with non-Hodgkin's lymphoma primarily affecting the orbital region were evaluated at Michael Reese Hospital and Medical Center, Chicago, between 1976 and 1983. Diagnoses were based on the histopathologic classification systems of the Working Formulation of the Non-Hodgkin's Lymphomas and Rappoport. Sequential staging procedures performed at the time of diagnosis included liver-spleen scans, Technecium-99 bone scans, gallium 67 scans, computerized axial tomograms of the orbit and abdomen, bone marrow examination and cerebral spinal fluid analyses. Adverse prognostic factors included the following: orbital bone erosions, Stage IV disease, and large cell or mixed cell, diffuse histologic features. The type of histopathologic findings combined with the results of sequential staging procedures is useful in identifying those patients who would benefit most from systemic chemotherapy.