• Fifteen patients with lysosomal storage diseases were studied. Diagnoses of their illnesses included infantile Gaucher disease; Krabbe disease; Niemann-Pick disease, type A; glycogen storage disease, type 2; Fabry disease, Jansky-Bielschowsky and Spielmeyer-Vogt types of amaurotic idiocy, GM, gangliosidosis, type 1; Hurler disease; and Sanfilippo disease, types A and B. We carried out ultrastructural examinations of skin biopsy specimens that were taken to establish a cultured fibroblast line on each patient. We found diagnostic storage inclusions in all patients except those with infantile Gaucher disease, Krabbe disease, and Spielmeyer-Vogt disease. This technique can be carried out on a specimen obtained by a primary physician on an out-patient basis, thus avoiding major surgery.