Metacarpal bone mass, bone mineral content in the forearm and bone mineral concentration were measured in 54 renal transplant recipients with a well functioning renal transplant a mean of 67 months after transplantation. Significantly decreased values of metacarpal bone mass, bone mineral content and bone mineral concentration were found. A highly significant correlation between metacarpal bone mass and bone mineral concentration was found in renal transplant recipients, probably indicating that changes in the amount of cortical bone and bone mineral occur simultaneously after renal transplantation.