Representative sections of normal lymph nodes, cases of reactive lymphadenopathy, and Hodgkin's disease were examined using two monoclonal antibodies reactive in paraffin sections using an immunoperoxidase technique. Antibody LN-1 recognizes B-lymphocytes in follicles; antibody LN-2 recognizes a broader spectrum of B-cells, and also shows positivity with some monocytes/histiocytes. The pattern of immunostaining with these antibodies is described with particular reference to Hodgkin The pattern of immunostaining with these antibodies is described with particular reference to Hodgkin and Reed-Sternberg cells. Some of the implications are discussed.