This paper examines service-learning case studies in Argentina, Mexico, and the United States. It analyzes whether Andragogy, the study of how to teach adult learners, is equally applicable and effective in different country contexts. First, we argue that service-learning is the most natural and appropriate teaching technique that aligns with the Theory of Andragogy. We then discuss how a clear understanding of Andragogy is the key to helping mature students process knowledge. Two cases of service-learning in an international context provide a research platform for examining differences in learning concepts, constructs, and student competences. We juxtapose Argentina and Mexico governance against U.S. governance, and we differentiate the public policy challenges within the two contexts. Our methodological approach employs grounded theory to identify themes of knowledge transfer through problematic environments. By comparing service-learning strategies in Argentina and Mexico vis-à-vis in the U.S., we find variations in assumptions of public administration practice, teaching methods, and student learning outcomes.