 Current practice guidelines for patients with acute low back pain LBP recommend a stepped care approach with initial treatment of education and advice to remain active. Referral to physical therapy is considered only when patients fail to recover after a few weeks. Recent research has led to the identification a subgroup of patients likely to experience rapid, pronounced, and sustained decreases in disability and pain with a brief manipulation and exercise intervention, suggesting it may be more cost-effective to manage this sub-group with early referral to physical therapy instead of the usual care approach. The integration of this evidence into routine practice has not been evaluated. We will assess the outcomes of integrating this evidence into the management of patients with low back pain. The study is a randomized trial, comparing management with early manipulation with the current care process model. Patients fitting the inclusion criteria will be randomized into one of two groups. One group will be managed with the current care process model. The other group will be managed consistent with the decision rule recommending early referral for a brief manipulation and exercise intervention during the first 4 weeks. Patients will be followed over 1 year. Outcomes will include measures of disability, pain, satisfaction, and direct medical costs. The study will examine the costs and effectiveness of integrating the alternative care model into practice. 