Problem-based learning (PBL) is a student-centred instructional approach in which complex real-world problems are used as the vehicle to promote students' learning of concepts and principles. This paper presents a case study that explored the learning experiences of 18 pre-service teachers and how the instructor was affected when implementing PBL in a course entitled "Principles of Instruction." Data-collection methods included multiple sources of evidence, such as reflective reports, interviews, participation observations, students' reports, and a questionnaire. Data analysis consisted of examining, categorising, and recombining quantitative and qualitative evidence to address the initial propositions of the study. This paper demonstrates how pre-service teachers' professional knowledge, learning engagement, reflective abilities, and teamwork were enhanced through the PBL approach, and that the quality of teaching also improved for the instructor. This study contributes to the professional literature on PBL in teacher-education courses, and may serve to encourage educators to implement PBL in their courses.