Understanding preceptors’ perceptions of an optimal Clinical Learning Environment (CLE) is essential to improving students’ clinical learning. The purpose of this study was to describe preceptors’ perceptions of what is needed to create an optimal hospital-based Clinical Learning Environment (CLE) for undergraduate nursing students. The specific aims of the study were to 1) explore preceptors’ assumptions of what constitutes an optimal CLE for undergraduate nursing students; 2) describe the factors that preceptors view as facilitators or barriers to optimal student learning; and, 3) describe the strategies that preceptors identify to create an optimal CLE.