We performed a pre-post study of the impact of three 90-minute faculty development workshops on written feedback from encounters during an ambulatory internal medicine clerkship. We coded 47 encounters before and 43 after the workshops, involving 9 preceptors and 44 third-year students, using qualitative and semiquantitative methods. Postworkshop, the mean number of feedback statements increased from 2.8 to 3.6 statements (P =.06); specific (P =.04), formative (P =.03), and student skills feedback (P =.01) increased, but attitudinal (P =.13) and corrective feedback did not (P =.41). Brief, interactive, faculty development workshops may refine written feedback, resulting in more formative specific written feedback comments.