The authors believe, with Benjamin Barber, that service to the neighborhood and to the nation are not the gift of altruists, but rather the duty of free men and women whose freedom is itself wholly dependent on the assumptions of political responsibilities (Barber 1992). Given the global world in which we live, however, we add the importance of international service to that of the neighborhood and nation. The authors, both professors at the University of Colorado-Boulder when this article was written, have spent considerable time in Africa and on other continents, working with schools and universities on the improvement of instruction in mathematics and other curricular areas. They detail some of those experiences, along with information about the University’s nationally recognized service-learning program, the International and National Volunteer Service and Training (INVST) program. Service-learning and volunteer activities have been part of our pedagogical repertoire for over three decades, and during that time we have been impressed by the impact of these multicultural and international experiences on not only ourselves, but also our students. Classroom learning has its place, but for powerful transforming learning, nothing has compared to the impact of these experiences on the life and learning of our students. In recent years, students have participated in “alternative spring breaks,” in addition to other international service-learning experiences.