There is an increased risk of developing cutaneous neoplasms in patients with renal transplants who are receiving immunosuppressive therapy. We studied 523 consecutive white patients who had received renal transplants at a Canadian medical center. Malignant neoplasms developed in 7.5% of these patients, and 72% of these neoplasms were cutaneous in origin. Compared with the general population, the rate of development of all skin cancers, squamous cell carcinoma, and basal cell carcinoma was 3.2, 18.4, and 1.4 times, respectively. In our study the squamous cell carcinoma to basal cell carcinoma ratio was 2.3:1, compared with 0.2:1 in the general population. There was no significant difference in the site of development of skin cancer in patients with renal transplants compared with the general population. There was, however, a propensity for the development of multiple skin cancers at an earlier age, especially on sun-exposed areas. The results of this study have been compared with those of other world medical centers.