Three patients with disseminated moniliasis were treated with intravenous injections of amphotericin B. Two were apparently cured. They previously had disseminated moniliasis following abdominal surgery. Both patients had received large doses of antimicrobial drugs and adrenal steroids prior to the onset of moniliasis. In the first case the fungi had direct access to the blood stream through indwelling intravenous polyethylene catheters; the mode of entry in the second was not established. A third patient with rheumatic heart disease developed fatal monilial endocarditis after mitral commissurotomy, the infection apparently having been introduced at the time of surgery. Each of the three strains of the offending organism isolated from the blood stream was inhibited by a small concentration of amphotericin B in vitro.