Community-based service learning is used in engineering and construction curricula to engage students in interesting, complex problems that benefit the community while developing competencies essential to professional practice. Service learning projects effectively expose students to issues otherwise difficult to teach, including critical resource constraints, tactics to overcome them, tradeoffs among possible solutions, systems integration, and organizational challenges of implementation. However, they are often underutilized due to the risks and challenges of integrating them into classes and managing student involvement. This paper explores the questions of what makes CBSL projects successful and the challenges faced by both faculty and students who participate in them. The findings are based on a literature analysis of challenges and a review of two service learning projects implemented by a conjoint senior level/graduate class on sustainable facility systems at Virginia Tech. Lessons learned are identified in three key areas: design as listening vs. design as inspiration, conflicting and unspoken objectives, and construction realities. Service learning projects offer a secure environment in which to learn about the challenges of construction, where the unexpected is an expected and valued part of learning. Through these experiences, students can better understand the tradeoffs required to pursue sustainability in capital projects and can better place sustainability objectives such as “minimize waste” and “reuse construction materials” in the context of what these objectives require in practice. These projects also offer benefits to clients in the community and afford the opportunity for civic engagement by students that may carry forward into their lives after graduation.