Emergency Departments (EDs) have changed in terms of their provided services as newer treatment options and medical technologies have become available. The demand on EDs is variable and ever increasing, often leaving them overcrowded. Many hospitals are utilizing triage algorithm to rapidly sort patients based on the severity of their injury or illness. To improve decision making and the productivity in EDs, researchers have implemented different tools and models from various fields. Group Technology (GT) is a management philosophy to improve manufacturing efficiency by sorting parts into part families. This book provides a framework for the definition, identification, and impact of patient grouping and prioritization on the ED static complexity and system performance. The output of this process represents a scientific basis for making informed and logical decisions to support improved ED patient sorting based on patient and treatment requirements information. The approach should be especially useful to researchers and professionals who may be considering utilizing engineering tools and methods to solve healthcare systems problems.