How many therapies can you think of, off the top of your head? Psychoanalysis probably, but you might also have heard of existential, humanistic, integrative, creative, and body therapies. And then there’s the therapies you might not have heard of like family constellations, internal family systems, transactional analysis, and gestalt therapy. But if you’ve tried to get therapy recently, particularly through a public healthcare system like the National Health Service in the UK or via Medicare in Australia, there’s a good chance you would only have been offered Cognitive Behavioural Therapy. That’s also what you’re most likely to have been recommended if you tried to access therapy through private health insurance or an Employee Assistance Program. I believe Cognitive Behavioural Therapy’s prevalence is not due to it being uncontroversially better than other therapies. Instead, it’s a complicated story about how we evaluate whether something works, what it even means to say it ‘works’, how medical research is funded and how decisions about which interventions to fund are made. It’s a story about Randomised Controlled Trials …