We present an unusual case of post-renal transplant 'erythrocytosis' in a patient with sickle-cell anaemia, who had developed renal failure following the effects of a phaeochromocytoma. Prior to transplantation, the patient had experienced only occasional crises. However, post-transplant, he experienced multiple and varied crises, associated with a significant increase in haemoglobin concentration. These symptoms were partially alleviated by regular venesection.