Many universities are investing in active learning strategies and learning spaces designed to support those strategies to increase student success. However, many instructors perceive barriers to adopting active learning techniques, limiting the effect of universities' investments. This research explored barriers to instructor adoption of active learning techniques and sought to expand the understanding of the differences in perceived barriers across academic disciplines, teaching experience, and other instructor characteristics. The first study in this research explored whether commonly stated barriers are indeed substantive barriers through a quantitative survey that asked instructors to rate the severity of each barrier. One commonly stated barrier, validated by this research, was the lack of available classrooms suited to teaching using active learning practices. In the second study in this research, observations were made of the behaviors of instructors and students in both lecture-style and active learning classrooms. The study explored how instructors overcame barriers related to the availability of suitable classrooms and investigated the ways in which the elements of both types of rooms supported active learning strategies. This second study found differences in student engagement within the two environments, with increases in engagement linked to specific affordances provided by elements of the active learning classrooms. Finally, recommendations were made for improving lecture-style classrooms with elements of active learning classrooms, including the addition of multiple writing surfaces and movable furniture, to assist instructors and students in the adoption of active learning techniques without requiring large investments by universities.