Conventional approaches to evidence that prioritise randomised controlled trials appear increasingly inadequate for the evaluation of complex mental health interventions. By focusing on causal mechanisms and understanding the complex interactions between interventions, patients and contexts, realist approaches offer a productive alternative. Although the approaches might be combined, substantial barriers remain.. To read the full article, log in using your MPFT NHS OpenAthens details. SSOTP (legacy account) - You can request a copy of this article by replying to this email. Please ensure you are clear which article you are requesting.