Objective: This study used a Theory of Planned Behavior (TPB) model to identify the factors influencing the future work expectations and outcomes of employees with a musculoskeletal injury.Participants: Australians with a compensable work injury (N = 174), mean age = 43.7 years, 53.2% male, 48.3% back injury, and 34.2% unskilled.Methods: A TPB model of the target behavior 'working, or continuing to work'three months from now' was constructed. A questionnaire measuring the model's components was completed at baseline and three-months follow-up. Results: The model met standard psychometric requirements. Attitude, Subjective Norm and Perceived Behavioral Control explained 76% of the variance in Behavioral Intention (R2= .76, p< .001). Behavioral Intention (the expectation to return to work) explained 51% of the variance in work participation at follow-up (NagelkerkeR2= .51, p< .001; sensitivity = 86.4%, specificity = 71.2%). The strength of key influences on expectations varied according to employment status, but included the availability of modified duties, social aspects of work, the opinion of the treating doctor, co-worker support, pain, and functional limitations.Conclusion: The TPB is a useful theoretical model and conceptual framework for identifying the influences on future work expectations and integrating the biopsychosocial determinants of return to work (RTW) found in the empirical literature.