There is a large economic cost associated with low back pain. In 1994 its cost to the United Kingdom (UK) was estimated by the UK Clinical Standards Advisory Group report to be nearly £6,000 million (ECU 8,350 million) annually. This principally consists of the indirect costs of lost production and disability payments rather than direct health service costs. A re-examination of the assumptions in the report shows that these costs appear to overestimate the economic cost of back pain by an unquantified, but possibly large, amount. This may restrict the benefit of introducing more effective treatments for back pain.