Objective: This study examined variables associated with having a once-only contact with the out-patient department of two community mental health services in Italy and Australia.Method: Two 8-year cohorts of patients, who had a new episode of care with out-patient psychiatric departments in South Verona and in Western Australia, were followed-up for 3 months after the first contact, to identify those patients who had no further contact with services. Potential determinants of once-only contact were analysed.Results: Thirty percent of new episodes of care for persons who met the inclusion criteria of the study were once-only contacts with the service in South Verona. In Western Australia, the figure was 24%. Moreover, the proportion of once-only contact patients has increased over time in South Verona whereas, in Western Australia, it has remained stable. In Western Australia, once-only contact patients were younger whereas in South Verona they tended to be older. At both research sites, patients who had a once-only contact were more likely to be male and to have a less severe mental illness.Conclusions: The results of this study suggest that only clinical characteristics were significant determinants of this pattern of contact with services consistently at both sites: the less severe the patient's diagnosis, the more likely the patient is to have a once-only contact. This may well indicate good screening at the initial point of contact by both sets of mental health service providers. Prospective studies are necessary to clarify the problem of 'once-only contact' and to organize a proper psychiatric care.