The above figure visually describes how the person, the task and the environment interaction define the worker’s performance and how this performance affects the worker’s productivity, safety and comfort. Understanding the interaction among people and other system elements leads to optimizing human well-being. The worker and system are co-responsible for the RTW outcome. The goal of the ergonomics is to fit the work to the worker and in rehabilitation, it refers primarily to interventions to reduce the physical and cognitive load of the work in order to match human limitations, which is generally decreased following a medical predicament.