We identified 80 patients with nephropathic cystinosis older than age 10 years in the United States and Canada. The oldest reported individual was 26 years of age. Ninety percent of patients had received at least one renal allograft. Age at the time of first transplant varied between 7 and 17 years (mean 10.0 years). Almost three fourths of the patients required thyroid replacement, 27% had splenomegaly, and 42% had hepatomegaly. Photophobia was noted in 86% of patients, decreased visual acuity in 32%, and corneal ulcerations in 15%. Neurologic involvement, renal osteodystrophy, and diabetes mellitus were unusual. All these late complications of nephropathic cystinosis contribute to a description of the natural history of the disease and provide a rationale for the therapeutic use of cystine-depleting agents after renal transplantation.