Background: Simulation in medical education offers the promise of safely and effectively preparing trainees for a variety of tasks encountered in clinical medicine. Purpose: The objective was to determine internal medicine (IM) clerkship directors' perceptions of the use of simulations during the medicine clerkship. Methods: A cross-sectional survey of 110 Clerkship Directors in Internal Medicine (CDIM) institutional members was presented. The survey contained 24 questions including multiple-choice responses with Likert scale and open-ended questions. Descriptive and correlational statistical analyses were performed. A thematic qualitative analysis was performed. Results: Response rate was 78% (86/110). Simulation was used in the IM clerkship in 84% (72) of responding schools. Simulations were used to teach a variety of clinical skills and concepts such as history taking and diagnostic reasoning. The intended goal of simulations was teaching in 39% (28), formative assessment in 49% (35), summative assessment in 38% (27), and compliance with Liaison Council for Medical Education requirements in 19% (14). Most of clerkships (54%, 49) use standardized patients, with 37.5% (27) using them for formative purposes, whereas 33% (24) used them for summative purposes. Support for simulation was provided by the school of medicine in 57% (41) of clerkships, by the department of medicine in 30% (22) of clerkships. Conclusions: Simulations are used to teach clinical skills and for formative and summative assessments. Standardized patients and simulation mannequins are the most commonly used simulations types. Further research is needed to assess clerkship directors' needs, knowledge, and use of simulation in specific learning and training contexts.