In immunocompetent patients, Mycobacterium avium/Mycobacterium intracellulare complex (MAC) has been associated with pulmonary infection in adults, cervical lymphadenitis in children, and disseminated infection in children and adults. MAC rarely has been recognized as a cause of localized soft-tissue infection in immunocompetent hosts. Six cases of granulomatous tenosynovitis due to MAC are reported; five cases occurred after local surgical procedures, trauma, or corticosteroid injection. In four cases, cure was achieved with combined medical and surgical intervention. In these six cases and 11 previously reported cases, both males and females were affected equally, usually in the fifth to seventh decades of life, and the distal upper extremity was predominantly involved. Surgical debridement with appropriate culture was critical for diagnosis and management. Antimycobacterial chemotherapy seemed to be a beneficial adjunctive measure in most cases but was clearly necessary for cure in only a few cases.