Adults in the UK with a diagnosis of either ICD-10 depressive episode or ICD-10 mixed anxiety and depressive disorder have been estimated to have taken more than a quarter of the total number of days of sickness absence in one year. Few patients receive effective treatment. There are four reasons for this: failure to seek help (40% don't attend); failure of GPs to recognise depression (30-50% of cases); non-adherence or early cessation of treatment (only about 25% of patients complete a six-month course of antidepressant treatment);lack of treatment efficacy (50% with moderate depression don't respond to initial treatment). Only about one in ten patients receive effective treatment.