In spite of the growing number of studies supporting the efficacy of psychological therapies for fibromyalgia, many issues need further development. For example, current treatment recommendations for this syndrome suggest that the intervention must be tailored to the psychosocial and functioning profile of patients. However, research is still needed in order to enable the identification of key factors for clinical improvement. Similarly, it is crucial to identify and assess idiosyncratic psychological characteristics that may allow the psychological intervention to be effectively adapted. In addition, an evidence-based description of the mechanisms involved in change at different levels (including psychological and physical ones) has not been developed yet.