Course-based undergraduate research experiences (CUREs) integrate an authentic research experience for students into a laboratory course. CUREs provide many of the same benefits to students as individual faculty-mentored research experiences. However, faculty experiences in teaching CUREs are not as well understood. There are no studies that compare faculty's anticipated experiences to actual experiences, and little comparison of the faculty experience by institution. Through interviews with eight biology faculty from four institutions, the faculty experience in implementing a CURE in an introductory biology laboratory was explored using qualitative analysis. Institutions included: a small, minority-serving, women's, primarily undergraduate university; a small, residential, primarily undergraduate college; a midsized doctoral university; and a large community college. Interviews were conducted at three time points: before professional development (PD), after the initial semester of teaching the CURE, and after teaching the CURE at least twice (1 year later). Faculty described resources, benefits, challenges, and feelings about teaching the CURE. However, anticipated experiences were often not the same as those actually experienced. There were also institutional differences in resources, benefits, challenges, and feelings. Implications for CURE PD include specific content such as strategies for teaching effective research group work, development of student proposals, and student time management.