Despite the significant amount of research on problem-based learning (PBL) in medical education and gifted education, there is only a scarce amount of research on this instructional approach in secondary mathematics education. The purpose of this study was to examine the perceptions of secondary school mathematics PBL facilitators on their facilitator training, classroom experiences, roles, skills, and implementation challenges. Survey data were collected from a sample of 41 facilitators who received PBL training from the Problem-based Learning Network (PBLN) of the Illinois Mathematics and Science Academy (IMSA). The findings revealed that a strong majority of participants indicated that their PBL training was effective at helping them understand the PBL philosophy, and the training provided them with sufficient insight into how they should manage the small group learning process. One major result indicated no statistically significant difference between mean roles scores and no statistically significant difference between mean skills scores based on level of facilitation experience. Qualitative findings indicated various challenges and difficulties facilitators perceived they faced while they planned for and implemented PBL into their classroom, including time constraints and curricular constraints. The qualitative results also indicated the majority of respondents found one or more roles of a PBL facilitator difficult or challenging, including managing the small group learning process. The results revealed that a small percentage of participants who received PBL facilitation training did not implement the instructional approach into their classroom while the implication from this finding suggested the need for additional training, professional development, and additional support from school administrators. Limitations related to the findings are reported and discussed, which includes the small sample size and the small number of problems scenarios some participants had facilitated.