Barcelona has been once again the meeting point of the latest advances in the management and research in Dual Pathology, which describe the comorbid presence of substance use disorders and other mental disorders. More than 2,000 professionals from over 70 countries met at the "http://www.cipd2015.com/" IV International Congress of Dual Disorders: Addictions and other Mental Disorders, chaired by Dr. Miguel Casas, head of the Psychiatry, Addictions and Mental Health group at Vall d’Hebron Institute of Research (VHIR). The congress offered 170 scientific activities, from workshops to symposiums and master classes. In these sessions, experts presented the latest studies on the treatment of dual pathology, clinical trials, biological biomarkers and therapeutic studies.Researchers from VHIR and the Vall d’Hebron University Hospital presented the results of a study about the consumption and addiction between patients over the age of 65, new psychometric instruments to assess compulsivity, a study about the differences of gender in alcoholic dual patients, a research about the importance of sleep disorders among patients addicted to drugs, and finally, a study about the borderline personality disorder and addictions. The congress took place at the Centre de Convencions Internacional de Barcelona, from the 17th to the 20th of April, and was organized by the "http://www.patologiadual.es/" Spanish Society of Dual Pathology (SEPD, in Spanish). Dr. Carlos Roncero, researcher from the Psychiatry, Addictions and Mental Health group, was the president of the organizing committee of this congress in which VHIR played a key role.