Using Simulation Education With Deliberate Practice to Teach Leadership and Resource Management Skills to Senior Resident Code Leaders. BACKGROUND: Cardiopulmonary arrests are rare, high-stakes events that benefit from using crisis resource management (CRM). Simulation-based education with deliberate practice can promote skill acquisition. OBJECTIVE: We assessed whether using simulation-based education to teach CRM would lead to improved performance, compared to a lecture format. METHODS: We tested third-year internal medicine residents in simulated code scenarios. Participants were randomly assigned to simulation-based education with deliberate practice (SIM) group or lecture (LEC) group. We created a checklist of CRM critical actions (which includes announcing the diagnosis, asking for help/suggestions, and assigning tasks), and reviewed videotaped performances, using a checklist of skills and communications patterns to identify CRM skills and communication efforts. Subjects were tested in simulated code scenarios 6 months after the initial assessment. RESULTS: At baseline, all 52 subjects recognized distress, and 92% (48 of 52) called for help. Seventy-eight percent (41 of 52) did not succeed in resuscitating the simulated patient or demonstrate the CRM skills. After intervention, both groups (n  =  26 per group) improved. All SIM subjects announced the diagnosis compared to 65% LEC subjects (17 of 26, P  =  .01); 77% (20 of 26) SIM and 19% (5 of 26) LEC subjects asked for suggestions (P < .001); and 100% (26 of 26) SIM and 27% (7 of 26) LEC subjects assigned tasks (P < .001). CONCLUSIONS: The SIM intervention resulted in significantly improved team communication and cardiopulmonary arrest management. During debriefing, participants acknowledged the benefit of the SIM sessions.