The potential of the immunogold-silver staining (IGSS) technique for immunophenotyping leukemia and lymphoma cells in cell smears was examined. Peripheral blood, bone marrow aspirates, lymph node biopsy specimens, fine-needle aspirates, and biologic fluids of 83 patients with acute or chronic leukemias, non-Hodgkin's lymphomas, or Hodgkin's disease were labeled. Cell smears, cytocentrifuge preparations, or imprints were fixed, incubated with the reagents, and counterstained with May-Grünwald-Giemsa. Stable immunostaining and good morphologic characteristics allowed accurate cell identification and rapid enumeration of the positive cells. The immunophenotypes obtained with the use of 35 monoclonal antibodies with different specificities were similar to those determined by flow cytometry or immunohistochemical studies on the same samples. This IGSS method was especially useful for the examination of poor samples or complex cell suspensions with rare malignant cells. It could be an alternative to the immunoenzyme methods that generally are used for this purpose.