Low back pain (LBP), a leading cause of disability, has been linked with profound economic, personal, and social costs (Hills 2006; World Health Organization 2003). This significant effect propels research in identifying modifiable risk factors that protract LBP; these factors can be targeted in early intervention (EI) (Pransky, Journal of Occupational & Environmental Medicine, 49(3):249–251, 2007; Schultz et al., Journal of Occupational Rehabilitation, 17:327–352, 2007, Journal of Occupational Rehabilitation, 18(2), 140–151, 2008; White et al. 2013). This randomized controlled study evaluated the effectiveness of two approaches, fixed versus flexible, in delivering proactive, interdisciplinary EI with 63 workers within a workers' compensation interdisciplinary case management setting (i.e., WorkSafeBC, Canada). Off-work 4 to 10 weeks post-back injury, the workers were also at risk of protracted work disability (N = 24 at high risk; N = 39 at moderate risk). Fixed, protocol-driven, interdisciplinary, multimodal, clinical, occupational, and case management-based EI was compared with a flexible, individual need-driven EI with the same modalities as the fixed approach. Results showed a significant narrowing of the outcome gap between the two interventions. High-risk injured workers tended to benefit more from a fixed, protocol-driven approach, as shown in the pilot study (Schultz et al. Journal of Occupational Rehabilitation, 18(2), 140–151, 2008). The results indicated that moderate-risk workers benefitted from a more flexible, need-based, individual, and low-intensity approach as compared with a fixed approach. The flexible approach for moderate-risk workers was also less costly and consumed fewer rehabilitation and health care resources. Recommendations for future research and practice included larger sample sizes, controllability of research interventions, risk for disability-EI matching, and conditions under which a flexible delivery of multimodal EI is more efficacious than a fixed approach, and vice versa.