This paper reports the results of a "cost-of-illness" study of low back pain (LBP) in Australian adults. It estimates the direct cost of LBP in 2001 to be AU dollars 1.02 billion. Approximately 71% of this amount is for treatment by chiropractors, general practitioners, massage therapists, physiotherapists and acupuncturists. However, the direct costs are minor compared to the indirect costs of AU dollars 8.15 billion giving a total cost of AU dollars 9.17 billion. LBP in Australian adults represents a massive health problem with a significant economic burden. This burden is so great that it has compelling and urgent ramifications for health policy, planning and research. This study identifies that research should concentrate on both direct but particularly the indirect costs including cost-effective management regimes that encourage an early return to duties.