This chapter focuses on the role of catastrophizing as a cognitive variable influencing chronic pain, particularly in fibromyalgia. It analyzes the main mechanisms and explanatory models of chronic pain, starting from initial models such as the fear-avoidance model or the stress model, and concludes by highlighting the importance of contextual models that seek to analyze the indirect role of pain catastrophizing in functional limitation, quality of life, and psychological well-being by the influence of positive and negative symptoms as depression and goals. The role of positive affect is postulated as a new contextual intervention where the individual’s role as an agent of their health implies a key to improving health. Identification profiles between patients is a key to the improvement of interdisciplinary treatment applications based on the symptomatology experienced in FM.