Fibromyalgia (FM) is one of the most frequent diseases causing chronic pain. Due to the heterogeneity of its clinical expression and the lack of standardized instruments to classify the signs and symptoms, the availability of a classification system would allow more homogeneous groups of patients to be identified and would permit individualizing diagnostic and therapeutic management. Correct classification of patients with FM requires individual diagnostic evaluation by a multidisciplinary team comprising the family doctor, a specialist in rheumatology or autoimmune diseases, a trauma doctor and a psychologist/psychiatrist. The diagnostic contribution of each specialist together with analysis of the timeline of appearance of signs and symptoms is essential in order to decide to which FM subgroup the patient belongs.