From June 1966 to December 1969, 11 prosthetic valves were inserted in ten patients at North Carolina Memorial Hospital because of valvular regurgitation complicating active infective endocarditis. Indications for operation included intractable heart failure, resistant infection, and repeated embolization. Operative mortality was 40%. One patient died 2½ years following operation from unrelated causes. The five survivors, 20 months to four vears following operation, are well and leading active lives. The predominant organisms were streptococcus and staphylococcus. Two of three patients with positive blood cultures one day prior to surgery and four of six patients with organisms demonstrated microscopically at operation are alive and free of recurrent infection for as long as 3½ years. This experience demonstrates that valve replacement is possible in the active phase of endocarditis if adequate antibiotic coverage is used and the focus of infection removed.