This study compared three forms of mail-mediated exercise behavior change strategies on the weekly leisure time exercise behavior of individuals at different stages of exercise (SOE). Subjects were 113 healthy females, 22 to 50 years old (M = 36.9). After being classified by SOE, subjects were randomly assigned to receive one of three treatments: lifestyle exercise packet (LEP); structured exercise packet (SEP); or control packet. Packets were mailed to subjects at their worksite. After 31-days, 108 (95%) subjects responded to a query about their previous week's leisure-time exercise behavior. A 3 (SOE) x3 (Exercise group) x2 (Time) REANOVA revealed main effects for SOE (p < 0.0001), exercise group (p < 0.05), and time (p < 0.0001). No significant interactions were observed. Post-hoc testing showed that those in the action/maintenance stages differed from those in the preparation and precontemplation/contemplation stages (p < 0.01), and that LEP subjects reported significantly more weekly leisure-time exercise post-intervention compared to controls (p < 0.01). These findings suggest the LEP was the most effective strategy for encouraging weekly leisure-time exercise. Future research should be directed at corroborating these findings and determining the potential long-term value of this strategy in comparison to more traditional strategies.