BackgroundIn Canada, the demand for mental health care exceeds the provision of services. This exploratory study aimed to assess the feasibility and impact of a new service delivery model for psychological consultations in primary care settings: the Single-Session Intervention (SSI), inspired by Advanced Access (AA) principles for appointment scheduling. The specific objectives were to examine whether the SSI increases accessibility to psychological consultations, to measure the effects of the intervention on different self-reported measures, and to assess users’ consultation experiences.MethodsParticipants were recruited in a University Family Medicine Group in Quebec (Canada), and the SSI was delivered by the on-site psychologist. No referral or formal diagnosis was needed to attend, and participants could promptly obtain an appointment. Participants rated the intensity of their problem, their level of psychological distress and their well-being, before and after the SSI. They also rated their satisfaction with their consultation experience. There was a follow-up 4 to 6 weeks later.ResultsOf the N = 69 participants who received SSI, 91% were able to obtain an appointment in less than 7 working days. The number of patients who were able to benefit from a psychological consultation was about 7 times higher after the implementation of SSI compared to previous years, when a traditional model of service delivery was in place. After SSI, participants felt that the intensity of their problem and psychological distress were lower, and that their well-being was increased, as indicated by significant pre-post test clinical measures (p < 0.0001). The observed effects seemed to be sustained at follow-up. Moreover, 51% of participants said that one session was sufficient to help them with their problem. Participants rated SSI as a highly satisfying and helpful consultation experience (92,9% overall satisfaction).ConclusionsSSI, offered in a timely manner, could be an innovative and cost-effective intervention to provide mental health services on a large scale in primary healthcare. Further research is needed to replicate the results, but these preliminary data seem to indicate that psychological distress may be quickly addressed by SSI, thereby preventing further deteriorations in patients’ mental health.Trial Registration2019–393, 26 March 2019.