Thirty-six patients treated for Hodgkin's disease (HD) or non-Hodgkin's lymphoma (NHL) who had been in complete remission and off all therapy for greater than two years were examined for evidence of immunosuppression. All patients were found to have marked depression of their lymphocyte blastogenic response to phytohemagglutinin (PHA) and of their skin test responses. No abnormalities of serum protein or immunoglobulins were found. T cells were significantly lower than normal in patients who had had Hodgkin's disease, but not in those who had had NHL. B cells, on the other hand, were significantly elevated in both groups. Splenectomy elevated the total lymphocyte count, while those who had not had a splenectomy had lower than normal lymphocyte counts. B cells were elevated while T cells tended to be lower in both splenectomy and nonsplenectomy groups, though only in the nonsplenectomized patients did this reach statistical significance. PHA response tended to be higher in patients with less advanced disease and less extensive treatment than in those with more advanced disease and more extensive treatment, although there was no statistically significant difference. Skin test response though, was shown to correlate well with both stage of disease at diagnosis and extent of treatment.