While Internet technologies show promise for changing behavior, new methods for engaging individuals are needed to maximize effectiveness. The aim of this study is to design and evaluate an Internet-delivered intervention for smoking cessation that encouraged seeking support from family and treatment from doctors. To evaluate different introductions to the Internet site. We conducted usability testing and analyzed server logs to trace user participation in the website. Two groups of users (current smokers) were recruited using Google advertisements. In Phase 1, 58% (75/126) of users accessed the self-management strategies, but few users accessed the social support (28%) and treatment-seeking modules (33%). Then, a brief motivational introduction was added, stating the proven effectiveness of content in the unused modules, low use of these modules, and recommendations by two doctors to use all modules. Compared with Phase 1, in Phase 2 the mean time spent on the website per session increased (8 to 18 min, p = 0.01) and use of the social support (50%) and treatment seeking modules (56%) increased (both p < 0.01). At 1-month follow-up, reports of talking to family about smoking cessation also increased from 84% to 100% (p = 0.038). Changing the rationale and context of Web-based health information using a motivational introduction can change user behavior. © 2008 Informa UK Ltd All rights reserved.