This 12-month study will enroll people with asthma. Participants will be randomly assigned to either the Asthma Feedback group or the Preventive Feedback (control) group. Both groups will log in to the study Web site at least once a month for 12 months and before all doctor visits. After logging in to the Web site, participants in the Asthma Feedback group will answer a series of questions about their asthma care. They will then receive information and feedback on the types of questions they should ask their asthma care provider during their next office visit. Participants in the Preventive Feedback group will answer questions and receive information and feedback regarding preventive services (e.g., cancer screening, cholesterol screening) that they should discuss with their primary care provider. At baseline and Months 6 and 12, all participants will complete online questionnaires regarding their asthma and overall health. Study researchers will review participants' medical records and insurance claims data at the end of the study.