Psychotherapy research: do we know what works for whom?

Clinical decision-making about suitability for psychological therapies is hampered by limitations of psychotherapy research and our lack of understanding of therapeutic mechanisms. Watzke et al's important randomised controlled study offers apparent validation for clinical judgement in relation to suitability for psychodynamic psychotherapy but also highlights the negative effects of unselected assignment to this type of treatment. Here, I consider why systematic selection for this form of treatment may be important and suggest how the limited effectiveness of psychodynamic therapy for an unselected group of patients may be addressed by more systematic treatment delivery and the ongoing monitoring of intermediate treatment outcomes.