The maintained antipsychotic efficacy of risperidone long-acting injectable (RLAI) was investigated in patients with schizophrenia or other psychoses who were transitioned directly from their previous antipsychotic medication. Patients symptomatically stable, but considered to require a treatment change, received 25 mg of RLAI (increased to 37.5 or 50 mg, if necessary) every 2 weeks for 6 months. Assessments included Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression–Severity (CGI-S), Global Assessment of Functioning (GAF), SF-36 Health-Related Quality of Life Questionnaire and Extrapyramidal Symptoms Rating Scale (ESRS). Of 1876 patients enrolled, 74% completed the 6-month study. The most frequent reasons for treatment change were non-compliance (38%), insufficient efficacy (33%) and side-effects (26%). There was a significant reduction from baseline to endpoint in mean total PANSS score and in the scores on all PANSS subscales and symptom factors (P<0.001). CGI-S improved significantly, as did mean GAF score, all factors on the SF-36 and patient satisfaction with treatment. Scores on ESRS showed significant, sustained improvements throughout the study period. Direct initiation of RLAI was effective and well tolerated. RLAI provides an advancement in the treatment options available for a wide range of patients requiring long-term antipsychotic therapy.