Introduction / Innovation Concept: Acute care skills are difficult to teach but can be improved using high-fidelity simulation training. We developed a comprehensive acute care “Nightmares-FM” simulation course (NM) for our Family Medicine residents and compared it to our standard simulation teaching- episodic Acute Care Rounds (ACR). Methods: NM course consisted of an initial 2 day session followed by 3 follow-on sessions interspersed throughout the PGY-1 year. ACR participants got access to 3 sessions interspersed throughout the PGY-1 year, each focusing on a different aspect of acute care. Both groups got access to the NM manual which covered the relevant topics: shock, arrhythmias, shortness of breath, altered level of consciousness and myocardial infarction. The manual is physiology-based and written specifically at the level that an average Family Medicine resident would be expected to perform at during on-call crises or emergency medicine rotations. 12 residents participating in the NM and 12 residents in time-matched ACR filled out questionnaires asking them to rate their level of knowledge of various aspects of acute care. Self-reported changes before and after each session, and at the end of the year, were analyzed using Wilcoxon matched pairs test. End of the year mean scores were compared using a two sided t-test. Finally, we developed a high-complexity acute care Objective Structured Clinical Examination (OSCE): COPD exacerbation with septic shock requiring use of positive pressure ventilation, fluids and vasopressors. The groups participated in the OSCE in February of their PGY-2 year and were graded using a validated scoring sheet marked by two independent expert video reviewers. Curriculum, Tool, or Material: NM initial 2-day session significantly improved the resident’s self-assessment scores on all 20 items of the questionnaire (p<0.05). Time matched ACR improved 11 out of 20 items (p<0.05) level. Follow-up NM sessions improved 5-8 out of 20 items, (p<0.05). Follow-up ACR sessions improved 1-5 out of 20 items, (p<0.05). End of the year means were higher for 13/20 items in the NM group (p>0.05) The NM group scored significantly higher on both the mean scores of OSCE individual categories: Initial assessment, Diagnostic workup, Therapeutic interventions and Communication and teamwork (p<0.05) and the Global Assessment Score (p<0.026). Conclusion: “Nightmares-FM” course is more effective than our standard curriculum at teaching acute care skills to Family Medicine residents.