Using an experimental and control group, this research measured the impact of the Reconnecting Youth in Iowa (RYII) prevention program on patterns of alcohol use among adolescents. Adolescents completed the Reconnecting Youth High School Questionnaire (HSQ) and the Government Performance and Results Act (GPRA) survey three times to assess students' patterns of alcohol use. Adolescents' gender, race/ethnicity, age, family SES comparison, positive parenting, peer deviancy, and friend influence were studied to help understand how they influenced alcohol use patterns. Treatment positively impacted peer influence to not use alcohol/drugs while peer deviancy and negative parental influence were correlated with more use. This study will help RYIII prevention personnel better understand factors influencing adolescent alcohol use and make appropriate curriculum changes in RYIII prevention programming.