Public health researchers and practitioners reporting findings from intervention studies seldom report in depth the processes of intervention development. However, such information would be useful for several reasons: (a) it would help guide the development of new interventions and refinement or revision of existing ones, (b) it would provide a framework and methodology on which other health practitioners and researchers could build, and (c) it would increase transparency of the development process and enhance the interpretation of the intervention's effects. The purpose of this article is to begin addressing the �black box� of Web-based intervention development by presenting the method for developing a Web-based, brief, motivational alcohol intervention program that has shown evidence of efficacy for college students, called Michigan Prevention & Alcohol Safety for Students. © 2011, Society for Public Health Education. All rights reserved.