The article proposes the 4-Es (namely Exposure, Explanation, Experience, and Evaluation) pedagogical model in empathy building that can facilitate moral development in students. This research reveals that the 4-Es pedagogy, which has been adopted in a university's service-learning course to study the living conditions of disadvantaged residents in urban Hong Kong, is largely effective as most students have expressed positive comments from their reflective journals and the pre- and post-program evaluation. Yet the actual efficacy is mediated by a number of factors which include the past experience of the students and the learning motivation.