The cardiovascular (CV) surgery department at Mayo Clinic is planning recovery bed (ICU and step down) needs for the next 10 years. While the current practice focuses on high service level (60% ICU utilization level), e.g., zero surgery cancelation, no shared rooms and no early discharges due to overloading; expected increasing patient volumes will require high level (system) planning in order to maintain the same level of care. A simulation model was developed to support quantitative decision making for the planning process. The model accounts for variability due to surgery scheduling (with seasonal effects), patient mix (with different growth rates), and patient length of stay (both in the ICU and the step-down unit). The model provides decision makers with a means to understand the relationship between patient service level and bed capacity/utilization level. It also provides a tool to evaluate the effects of proposed clinical and process improvements.