In 1996, the then Newcastle and North Tyneside Health Authority established a Clinical Effectiveness Unit. The remit of the Unit was to provide support to local health care teams in primary and secondary care, with the aim of promoting clinical effectiveness and encouraging the use of best evidence in daily practice through systematic, evidence-based approaches to guideline implementation. The strategy adopted by the Clinical Effectiveness Unit was to concentrate on five clinical areas. These were selected by a multi-disciplinary steering group using explicit criteria (evidence of inappropriate variation in practice; a good evidence base for what should be done; the clinical area should be a source of significant morbidity or mortality; large cost implications in the management of the topic). Depression was one of the clinical areas chosen.