Results showed that within the themes of human relation, lived body, lived time, lived things, and lived space, subthemes of student's characteristics (preparedness, motivation, and confidence), preceptors' characteristics (expectations, trust, feedback), site characteristics (documentation and EMR; preceptors; providers, staff, and resources; patients and patient care complexities), and time (clinical schedule and time to teach) were present. The key factors in fostering students' professional autonomy development were preceptor trust and their entrustment decisions.