Problem-based learning (PBL) is a student-centered educational method to enhance interactive and integrated learning through small group activities. In the 1994 academic year, the Faculty of Pharmaceutical Sciences, Prince of Songkla University, started implementing PBL in the Dispensing Pharmacy Laboratory course for fourth year students. In the 2002 academic year, PBL was further introduced into Pharmacognosy I for third year students and Pharmacognosy II for fourth year students, as well as Modern Pharmacognosy courses. The purpose of the present study was to survey the understanding and opinions of pharmacy students as well as facilitators of the PBL teaching-learning practice. The subjects were fourth (N=112) and fifth (N=101) year pharmacy students, plus 19 faculty members who had served as PBL facilitators in the Department of Clinical Pharmacy and Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Prince of Songkla University. Learning and teaching methods in the PBL courses were described. A questionnaire was designed to determine the following: (1) understanding of students and facilitators of the PBL process, facilitator roles, and student roles; and (2) opinions of students and facilitators on the PBL process. The self-administered questionnaires were scored on a Likert scale rating and check-list, designed separately for students and facilitators. The overall response rates were 66% and 53% for students and facilitators, respectively. The questionnaire survey showed that 73% and 85% of fourth and fifth year pharmacy students, respectively, had good understanding of the PBL, while 90% of facilitators, had the understanding at an excellent level. In contrast, 32% and 57% of fourth and fifth year pharmacy students, respectively, and 10% of facilitators had a very poor understanding of facilitator roles. Several positive and negative aspects of the students’ and facilitators’ opinions were revealed. For both student and facilitator PBL received its highest ratings in the areas of student-facilitator-interaction, autonomous learning, critical thinking, and two-way communication. The lowest rating was in the area of time consumed. Overall, they suggested that more PBL should be incorporated into the curriculum. The study results showed both students and facilitators identified both pros and cons with the PBL teaching method. The results also indicated a need to provide more orientation on the PBL process and roles of facilitators and students.