Abstract: This article expands current knowledge of the impact that brief but intense religious experiences can have on routine behavior by examining the long-term effects of short-term mission travel on both volunteering and charitable giving. Existing literature addresses only the first few years after travel. Using data from the 2005 Religion and Global Issues Survey, I examine how participation in a domestic or international religious mission trip in high school influences adults’ volunteering and giving behavior. I also consider alternate explanations that may account for the relationship between high school mission-trip participation and current giving or volunteering, including demographic factors, religious beliefs and practices, and other forms of civic engagement. I find adolescent participation in a domestic short-term mission trip has a significant, positive influence on the likelihood of volunteering for either a local or an internationally focused organization as an adult. In contrast, adolescent participation in a domestic mission trip has a significant dampening effect on charitable giving to secular organizations. I find no significant associations between international high school trips and adult volunteering and giving when additional factors are taken into account. I discuss the implications of these results for the ways church leaders and scholars think about the mechanisms through which brief, transformative religious experiences influence beliefs and behavior over the course of a lifetime.