The first cluster of the CANSAS network consists of projects with a focus on potential mediators between CAN and SUD in adult life. The project ‘Trauma, ER and substance-use disorder: does emotion dysregulation moderate the association between trauma and substance use/relapse?’ (PI Sven Barnow, Heidelberg) examines the mediating role of ER in the relationship between CAN and SUD. To this aim, N = 80 male and female healthy individuals with a history of CAN are compared with N = 160 SUD patients of both genders with such a history using different methodological approaches. This also includes ecological momentary assessment (EMA) to collect real-time data about subjects’ emotional status and ER strategies as they go about their lives within their normal environments. It is expected that traumatized SUD patients show ER deficits (e.g. more often use rumination, avoidance and less often reappraisal, show inflexibility) compared to traumatized healthy controls. Moreover, it is expected that ER deficits are related to characteristics of substance use as well as craving/relapse in currently abstinent traumatized SUD patients.