There is a large body of research examining work disability management and the return to work (RTW) of sick or injured workers. However, although this research makes clear the roles of the returning worker and supervisor, that of the co-workers is less well understood. To increase understanding of this topic, we have identified, reviewed, and discussed three studies that emerged from our connection with a Canadian research-training program. The first study, conducted in Sweden by Tjulin, MacEachen, and Ekberg (2009), showed that co-workers can play a positive role in RTW, but this is often invisible to supervisors. The second study, undertaken by Dunstan and MacEachen (2013) in Canada, found that RTW could both positively and negatively impact co-workers. For instance, co-workers may benefit from learning new skills, but may also be burdened by the need to assume extra work to accommodate a returning worker. The third study, performed in Belgium by Mortelmans and Verjans (2012) and Mortelmans, Verjans, and Mairiaux (2012) reported the need to include the expectations and objections of co-workers in RTW plans and implemented a three-step RTW tool that involves co-workers. Taken together, these studies highlight the social context of work, the positive role played by co-workers in the RTW process, the impacts of workplace social relations on RTW outcomes, and the benefits to all of involving co-workers in RTW plans.