The primary goal of this project is to develop a computerized screening program for primary care offices that is based on the NIAAA's new Alcohol Screening Guide for Children and Adolescents and assess its psychometric properties among nine- to 18-yr-old primary care patients. There is substantial evidence supporting the effectiveness of screening and brief intervention among adult primary care patients, primarily in the reduction of harmful drinking. However, there have been few studies of alcohol screening and brief intervention conducted among adolescents seen in busy primary care settings. This project will develop and validate a new computerized Alcohol Screening for Children and Adolescents (cASCA) program which incorporates the age-specific screening questions of the NIAAA Guide and includes the CRAFFT and AUDIT as secondary risk/problem assessments. We will add tobacco screening because tobacco use is the leading cause of cancer-related mortality in the US as well as screening for marijuana and other drug use so as to create a comprehensive screening instrument that includes all major substances that adolescents use.