Data from the National Center for Health Statistics were used to analyze the number of orthopaedic operations that were performed in the United States in 1979, 1981, and 1983. During the study period there was an increase of 24 per cent in the total number of orthopaedic procedures. During the same five-year period, the number of orthopaedic surgeons increased 28 per cent. Orthopaedic surgeons performed 3,549,000 operations in 1983, the most common orthopaedic procedure being open reduction and internal fixation of a fracture (331,000). This was also the eleventh most common operation performed in this country in 1983. The number of arthroscopic procedures (260,000) increased 100 per cent during the period of study, and this procedure was the sixteenth most common operation performed in the United States. In 1983, orthopaedic operations comprised 19 per cent of the surgery performed in this country. These figures illustrate the dynamics of the operative practice of orthopaedic surgeons in the United States. The figures show that the number of orthopaedic operations has markedly increased over the five-year period, but this increase is not as great as the increase in the number of orthopaedic surgeons. Future individual operative workloads of orthopaedists will decrease if these trends continue.