Despite the numerous benefits of physical activity for patients with diabetes, most healthcare providers in busy clinical settings rarely find time to counsel their patients about it. A Web-based program for healthcare providers can be used as an effective counseling tool, when strategies are outlined for specific stages of readiness for physical activity. Seventy-three adults with type 2 diabetes were randomly assigned to Web-based intervention, printed-material intervention, or usual care. After 12 weeks, the effects of the interventions on physical activity, fasting blood sugar, and glycosylated hemoglobin were evaluated. Both Web-based and printed material intervention, compared with usual care, were effective in increasing physical activity (P < .001) and decreasing fasting blood sugar (P<.01) and glycosylated hemoglobin (P < .01). Post hoc analysis for change scores indicated significant differences between Web-based intervention and usual care and between printed material intervention and usual care, but not between web-based and printed material intervention. The findings of this study support the value of Web-based and printed material interventions in healthcare counseling. With increasing Web access, the effectiveness of Web-based programs offered directly to patients needs to be tested.