Early medical management of cumulative trauma disorders (CTDs) in the semiconductor industry was described. In 1987, there were 72,940 reported cases of CTD, according to the Bureau of Labor Statistics. Worker compensation claims for CTDs increased 300% since 1987. The general principles of ergonomics were briefly described and CTDs were defined. The development of CTDs, factors resulting in the dramatic increase of CTDs, and industries and occupations at high risk were discussed. A preventive strategy including engineering, administrative, and medical management controls was presented. CTD usually occur in upper extremities in workers who have jobs which require repetitive, forceful movements, in awkward or static positions, with the use of vibrating tools. Workers with highest CTD risk are meat packers, dental hygienists, data entry keyers, hand grinders and polishers, miscellaneous hand workers, and typists. Medical management of CTD involves early recognition, evaluation and treatment of CTD, plus surveillance, conditioning, and rehabilitation programs. Conservative therapy includes heat or ice, nonsteroidal antiinflammatory drugs, physical therapy, and splints. The author concludes that CTD are painful conditions that can progress to crippling disorders in workers, and increase costs to employers for workers' compensation claims and lost productivity.