Preparing health care professionals for challenging communication tasks such as delivering bad news to patients and families is an area where a need for improved teaching has been identified. We developed a simulation-based curriculum to enhance the skills of health care professionals, with an emphasis on the communication of difficult or bad news, which we termed relational crises. Our approach was based on a review of existing simulation-based curricula, with the addition of unique features, including a learner-focused needs assessment to shape curriculum development, use of 360-degree evaluations, and provision of written feedback. Development and implementation of our curriculum occurred in 3 phases. Phase I involved a multidisciplinary needs assessment, creation of a clinical scenario based on needs assessment results, and training of standardized patients. In Phase II we implemented the curriculum with 36 pediatric and internal medicine-pediatrics residents, 20 nurses, and 1 chaplain. Phase III consisted of the provision of written feedback for learners, created from the 360-degree evaluations compiled from participants, observers, faculty, and standardized patients. Participants felt the scenarios were realistic (average rating of 4.7 on a 5-point Likert scale) and improved their practice and preparedness for these situations (average rating, 4.75/5 and 4.18/5, respectively). Our curriculum produced a statistically significant change in participants' pre- and postcurriculum self-reported perceptions of skill (2.42/5 vs. 3.23/5, respectively, P < .001) and level of preparedness (2.91/5 vs. 3.72/5, respectively, P < .001). A simulation-based curriculum using standardized patients, learner-identified needs, 360-degree evaluations, and written feedback demonstrated a statistically significant change in participants' self-perceived skills and preparedness for communicating difficult news in pediatrics.