The development of a Web-based parent-focused intervention to improve parental awareness and monitoring of adolescent alcohol use was preliminarily evaluated. Upon completion of baseline assessment, 67 parents were randomly assigned to the experimental Web-based parent-focused intervention or an assessment-only control condition. Participants who completed the experimental program, relative to control participants, significantly improved knowledge of problems related to underage drinking (p < 0.01) while improvements in overall monitoring of their children approached significance (p = 0.08). Improvements in monitoring by experimental participants, relative to controls, were pronounced in phone monitoring (p < 0.01) and indirect monitoring (p = 0.05). Participants in this study improved their communication about alcohol from pre- to post-intervention regardless of intervention. There were no statistical between-group differences found regarding underage drinking attitudes. This pilot evaluation demonstrates that this program warrants further examination in controlled trials with greater power. Study implications are discussed in light of results.