Fifty-eight teachers of grades 1-12 in 10 schools located in two rural and three urban school divisions in Manitoba were involved in a study implementing the Three Block Model of Universal Design for Learning and exploring its outcomes for teachers and students. This article reports teachers' perceptions related to the outcomes of the implementation of the model for both students and themselves and gives voice to teachers working in challenging, diverse classrooms regarding the barriers they face to inclusive practice and what supports are needed. After implementing the model, teachers reported positive student outcomes in terms of reductions in challenging behaviour, improved student-to-student interactions, engagement, and learning. They also believed the model improved their practice and self-efficacy related to inclusive education, reduced their workload, and improved job satisfaction. However, teachers also articulated several barriers to its implementation, including the need for collaborative planning time, differentiated resources, professional learning communities, and public education.