Jlmbulatory monitoring of signals, related to cardiovascular system per­ formances, is one of the biomedical technologies of wider interest. This interest is well documented by the literature, by the number of instruments available on the market and by the increasing diffusioo of this technique at routine clinical level. The wide distribution of ambulatory monitoring is however not yet well supported by commonly accepted criteria of clinical interpretation, by an assessment of the minimal requirements for instrumentation performances, or by indications of costjbenefit figures in relation to different situations. Several European centres have a recognized expertise and are well suited to the examinatioo of the problem of defining comnon guidelines and of making recommendations so as to stimulate an improvement of the clinical usage and of the performance of the instrumentation. The Biomedical Engineering Standing Group of the Committee for Medical and Public Health Research approved the organization of this \\Orksrop which had as its aims the assessment of the state-of-the-art of different aspects of ant>ulatory monitoring and the discussion within a group of experts of the feasibility and interest in promoting the coordination in Europe of these activities in the frame\\Ork of a "concerted action". The \\Orkshop was held in Pisa over two full days (April 11-12, 1983). The participants were physicians and engineers, experts in their fields.