--- - |2+ This paper updates previous similar reviews published in JFT in 2000, 2009 and 2014. It presents evidence from meta‐analyses, systematic literature reviews and controlled trials for the effectiveness of couple therapy, family therapy, and systemic interventions for adults with a range or relationship and mental health problems. The evidence supports the effectiveness of systemic interventions, either alone or as part of multimodal programmes, for relationship distress, psychosexual problems, intimate partner violence, anxiety disorders, mood disorders, alcohol problems, psychosis and adjustment to chronic physical illness. - Journal of Family Therapy, EarlyView.