Psychosocial factors have been shown to be major determinants in the return to work of individuals with chronic back pain. It is important, therefore, for occupational therapists to have an understanding of these factors and to include an evaluation of them when assessing function for work. This article presents an overview of the influence of some of these factors on function and, in particular, return to work in individuals with chronic back pain. It also provides an introduction to tools occupational therapists may use to assess these factors within a comprehensive functional capacity evaluation. Variables discussed include perceived disability, expectation of return to work, self-efficacy, perceived effort, pain intensity, pain location and pain behaviour. Consideration is given to the reliability and validity of the tools reviewed.