This case study examined students' and the instructor's perceptions of active learning classrooms (ALC) as well as their interactions in a class in a Midwestern university. Data were gathered from classroom observations and semi-structured interviews with faculty and students in a graduate-level course. Thematic analysis was used to analyze interview data; and inductive content analysis was used to analyze the weekly video recordings. The results showed that the active-learning classroom was perceived as more flexible environment for movement and communication in small groups than that in the traditional classroom. The implications for the active learning classroom design were provided.