This paper describes the development and a preliminary usage analysis of a novel Internet-based support system that assists cancer patients in symptom monitoring and disease management. The system, called WebChoice, allows patients to monitor symptoms over time, and provides access to evidence-based self-management options tailored to their reported symptoms as well as a communication area where patients can ask questions to a clinical nurse specialist and exchange experiences with other cancer patients. A currently ongoing randomized clinical trial evaluates effects of WebChoice on patient outcomes. This paper describes essential features of WebChoice, steps we used to design it as user-friendly as possible; and preliminary findings on patients use.