Since 1995, TeenNet Research (www.teennet.ca) has been a leader in developing strategies for involving youth and adults in co-creating e-health-promotion Web sites and behavior-change programs. In this article we review TeenNet's experience and lessons learned from more than a decade of action research with youth, with an emphasis on the guiding frameworks for participatory action research and Web-site creation and evaluation. The models are applied to the Smoking Zine (www.smokingzine.org), a 5-stage Web-assisted tobacco intervention, which is profiled with regards to its development, evaluation, and dissemination, including results from a school-based randomized, controlled trial. The prospects for using information technology to engage youth in health promotion are discussed in relation to TeenNet's past work and future interests in new Web 2.0 technologies.