The effect of external inspection systems on the quality of care remains unclear and the evidence is contradictory. Studies have demonstrated a positive association between accreditation and the ability to promote change, professional development, quality systems, and clinical leadership. There is evidence to support an association between inspections and different quality outcomes e.g. reduced incidence of pressure ulcer and suicide. There are however also studies reporting that inspections have no impact on the quality of care. Inspection systems are widely used and much resources are spent on such systems worldwide. More knowledge about how and whether external inspections can effect the quality of care is needed.