In this paper we communicate our experience with 60 patients who suffered two or more episodes of infectious endocarditis (IE), selected from 1053 cases of IE defined in accordance with Duke's Hospital criteria. Relapsing IE was diagnosed when episodes occurred with at least a 6 month interval between them or when, even if the time distance was shorter, they were caused by different microorganisms. Sixty-four cases of relapsing IE were observed. In each patient we considered age, sex, presence of risk-factors for IE, time laps from the onset of symptomatic disease to diagnosis, time interval between the two or more IE episodes, aetiology, endocarditic location, echocardiographic elements, therapy, complications and final outcome were considered. We conclude, agreeing with other authors, that infectious endocarditis may rightfully be considered a risk factor for further IE episodes and that, for this reason, an adequate prophylactic therapy must be given.