Emergency Departments (EDs) across the United States struggle to deliver efficient care in a timely manner. Factors such as increasing patient volumes, a reduction in the number of EDs, and higher inpatient census appear to be creating EDs that are overcrowded (American College of Emergency Physicians [ACEP], 2016; American Hospital Association [AHA], 2017). The consequences of overcrowded EDs combined with extended wait times create a significant quality and safety issue for EDs (Newell et al., 2011; Pines, 2006; Richardson, 2006; Sun et al., 2013). The purpose of this quantitative non-experimental before and after study utilizing retrospective data was to determine if the implementation of a Split Flow Model of Care for ambulatory ED arrivals would impact the median length of stay (MLOS) for discharged patients and the left without being seen (LWBS) rate. Data was collected from two separate six-month time frames before and after the implementation of the Split Flow Model of Care. A Kruskal-Wallis Test failed to demonstrate statistical significance between the MLOS for discharged patients and the LWBS rate before and after the Split Flow Model of Care was implemented. However, the study demonstrated clinical significance when the LWBS rate decreased 61 percent between the two time periods. This decrease occurred despite an increase in patient acuity and an increase in ED patient boarding during the six months following the implementation. This study outcome offers other nursing leaders, healthcare organizations, and emergency departments the opportunity to learn new strategies to impact LWBS rates despite overcrowding challenges in emergency departments.