For the fourteenth consecutive year the Vall d'Hebron Campus has hosted the 14th Session of Advances in Chronic Fatigue Syndrome, coordinated by Dr. José Alegre, responsible for research on chronic fatigue in the Vall d'Hebron Research Institute (VHIR). Coinciding with the day of these diseases, the Conference was held on 11 and 12 may in the hall of the Pabellón Docente of the Vall d'Hebron University Hospital.The scientific session has focused on the latest advances in the study of Chronic Fatigue Syndrome, Fibromyalgia and Multiple Chemical Sensitivity from primary care, the work incapacity and the effects on quality of life. The keynote, by Dr. Eduardo Rodríguez-Farré, focused on the neurotoxicity of environmental pollutants (xenobiotics) and their involvement in patients suffering from multiple chemical sensitivity.According to Dr. Alegre, "they are taking strides in knowledge and aetiologic factors of the severity of chronic fatigue in its full context". Advances that are possible thanks to the help of new technologies and the inclusion of multidisciplinary working groups in different areas.The Session, a national benchmark, has counted with first level specialists to expose relevant issues in relation to the diagnosis from primary care. Also discussed aspects related to the quality of life of these patients, which involves an important functional limitation and poor quality of life, both in physical and mental activities, in the form of work incapacity in the adult, and school failure in infant and in adolescents.On the other hand, the Session also addressed relevant aspects of the assessment of the implication of vitamin D deficiency and the severity of clinical symptoms in these diseases.Between the two sessions, was presented the testimony of a patient with a severe impairment of chronic fatigue and fibromyalgia, as well as the platform of the web of the Association DOLFA, the first Association in Spain of relatives of children and adolescents with these diseases to disseminate and promote clinical and biomedical research.The session culminated with a seminar conducted by Dr. Uldis Berkins (Director of Research, University of Riga) and the Professor Modra Murovska (Director, August Kirchenstein Institute of Microbiology and Virology (RSU), in Latvia), both European authorities in this field, and specialized in the European network EUROMENE and the involvement of the viral infections in chronic fatigue syndrome.