Some of the experimental, pathologic, and clinical features of extremity compression are reviewed with special reference to vulnerability of peripheral nerves to compressive forces at specific anatomic locations. Attention is directed toward syndromes resulting from mechanical factors, and it should be pointed out that a nerve can be compressed at more than one level. Localized peripheral nerve compression is common in clinical medicine; carpal tunnel syndrome is the most common example. Physicians who maintain a high index of suspicion to the signs and symptoms of peripheral nerve compression will diagnose and treat these conditions earlier and thereby reduce the number of patients who develop permanent functional disabilities.