Study Design: A case-control study involving parallel benchmarking audits was conducted. Objective: To compare the safety, efficacy, and cost effectiveness of evidence-based medical care and usual care for acute low back pain. Summary of Background Data: Although several sets of guidelines have been promoted for the management of acute low back pain, there is no evidence that following guidelines results in better outcomes. Methods: Special clinics were established, at which trained medical practitioners managed patients with acute low back pain according to evidence-based guidelines. Their outcomes were audited by independent research nurses. Meanwhile, and separately, the outcomes of patients managed by their own general practitioners were audited by research nurses using the same instruments of assessment. Results: In both settings, patients showed remarkable degrees and rates of recovery, with low rates of recurrence. However, evidence-based medical care resulted in a significantly lower cost of treatment; a significantly greater reduction in pain, sustained at both 6 and 12 months; significantly fewer patients requiring continuing care at 3, 6, and 12 months; a significantly greater proportion of patients fully recovered at 12 months; and significantly greater proportions of patients rating their treatment as extremely helpful and offering positive, unsolicited comments about their treatment. Conclusions: The immediate results from evidence-based care are marginally better than those from good usual care, but in the long term, evidence-based care achieves clinically and statistically significant gains, with fewer patients requiring continuing care and remaining in pain. Consumers approve of evidence-based care.