The clinical characteristics of infections due to bacteroides with emphasis on musculoskeletal involvement were reviewed together with data on eleven patients with musculoskeletal infections due to bacteroides seen at the Mayo Clinic over an eighteen-year period. Six of these patients had osteomyelitis. All cases were characterized by a chronic course prior to bacteriological diagnosis. Follow-up indicated that the infection was arrested in ten of eleven patients after extensive débridement and antibiotic therapy.