Facilitators oversee the dynamics during the Problem-Based Learning (PBL) process. Students are engaged in PBL by helping each other during the learning process, and facilitating such a process requires knowledge, experience, and strategic thought. An effective facilitator knows when and how to intervene by guiding without conveying the answers to specific questions. The role of the PBL facilitator is vital. This chapter discusses how to facilitate to ensure the cohesiveness and smooth flow of PBL group sessions.