PROJECT SUMMARY/ABSTRACT: Dentists regularly encounter patients experiencing problematic substance use and recognize the importance of screening for substance abuse; however, they have limited exposure to addictions training and generally lack systems to aid in screening, intervention, and referral to addictions treatment. Several critical gaps exist in our foundational knowledge regarding dentists’ implementation of SUD screening. First, most prior work in this area has focused on implementation of tobacco, alcohol, and – more recently – opioid screening, with very little work addressing dentists’ implementation of screening for other substances of abuse, particularly cannabis and stimulants. Second, except for recent studies specific to opioid screening, most work in this area is dated by nearly a decade. Third, very little information exists regarding implementation of brief counseling, referral to treatment, or willingness to engage in other point-of-care interventions addressing substance misuse and its associated harms. Finally, and perhaps the most notable gap, is the lack of information regarding dentists’ training, motivational factors, and practice behavior related to screening implementation with adolescent patients. To address these gaps, the Substance Use Disorders Screening (SUDS) Study will conduct a national survey of dental practitioners’ substance use screening practices among adolescent and adult patients through the Network. Results of this survey will speak directly to implementation gaps and will inform the development of training and implementation interventions that provide dentists with the necessary tools to implement universal substance use screening, brief interventions, and referral to treatment (when appropriate) confidently and competently. The Network Coordinating Center for the National Dental Practice-Based Research Network will provide scientific, technical and administrative support for the development, implementation, analysis and dissemination of the SUDS Study.