The clinical course of 70 patients with tuberculous peritonitis seen over a 43 year period has been reviewed. Thirty-seven patients were diagnosed prior to the advent of anti-tuberculous chemotherapy and 33 after. Clinical manifestations remained unchanged over the period of study. Abdominal pain (93%), fever (63%), gastrointestinal upset (60%), weight loss (60%), and ascites (59%) continue to be the most common findings. Females outnumbered males 2:1. In 89% of patients the duration of symptoms prior to diagnosis was a week or longer, and in 47% it was longer than a month. Diagnosis was confirmed by histologic examination of intra-abdominal tissue in 44% of cases, by clinical suspicion with an extraperitoneal site of tuberculosis in 29%, by bacteriology of peritoneal fluid in 24%, and by autopsy alone in 3%. An extraperitoneal site of tuberculsis was present in 83% of patients. The importance of obtaining a definitive diagnosis, and of instituting immediate antimicrobial therapy is emphasized by the mortality of 49% in the pre-antibiotic era, and of 7% in patients receiving anti-microbial therapy. The conclusions from this review are that: 1) with suggestive clinical manifestations and bacteriologic proof of active tuberculosis anywhere in the patient, operation is not mandated; 2) in the presence of the above clinical manifestations, and in the absence of definitive bacteriologic proof, exploratory laparotomy is indicated for diagnostic purposes; 3) antituberculous chemotherapy is highly effective, and is the treatment of choice.