Introduction: Assertive community treatment (ACT) is an alternative care to hospitalization to avoid the revolving door in cases of patients suffering from severe mental disorders. The implementation and care provision by ACT teams evidence significant variance in the fidelity to the original model. The lack of a general framework and standardization of care provision could compromise the replicability and comparability of these studies, showing controverse results worldwide. In Europe, hybrid versions of ACT teams, or Assertive Outreach Community Teams (AOCTs), are being implemented without standardization. Many of those mental health systems have failed to provide adequate care, compromising the efficiency of AOCTs. This research aims to assess the of AOCTs in the mental health system of Bizkaia (Basque Country, Spain). Methods: The sample consisted of 19 catchment areas in Bizkaia (Basque Country, Spain). This mental health system is a community care-based model that integrates hospital and community care services. It has 5 AOCTs, which provided care to 317 AOCTs users. Input variables included services, places, psychiatrists, nurses and psychologist in AOCTs. Outputs were the number of visits, prevalence, length of stay, discharges and readmissions. The EDeS-MH decision support system was used to assess the AOCTs performance. Results: Findings showed that the AOCTs were performing efficiently in terms of decreasing readmissions and length of stay at inpatient care. On average, the relative technical efficiency oscillated from 0.91 to 0.90, which evidenced that there was a good management of the available resources, avoiding the revolving door phenomenon and proving aftercare when users are discharged from hospital. Discussion: AOCTs in Bizkaia are performing in an efficient way by decreasing number of admissions, length of stay and readmissions at inpatient care. In addition, this type of care plays an essential role to avoid overloading on acute day hospital care and non-acute hospital care services.