This book presents an advanced systematic mapping review (SMR) and state-of-the-art taxonomy of emergency departments (EDs). Focusing on the patients' level of fulfilment and how it can be enhanced, it examines existing problems like waiting periods and overcrowding and how these can be alleviated to provide a better service. The author examined research papers from 1964 to 2018, and developed six research questions, organising them using mapping studies, the primary objectives of which were firstly, to obtain a common understanding of the problems that need to be highlighted in EDs, and secondly, to re-analyse the methods used. Focusing on quality, the book encourages citations of experimental methods from important studies concerning EDs that can improve services. Through different research papers, various thematic areas in the healthcare sector were examined, like the determination of the relative efficiency of pre-discharge interventions; the analysis of care and managing common indications during the last stages of life; using e-Health to enhance effectiveness and proficiency; the seriousness of patient differences among EDs; the identification of quality problems in healthcare contexts; existing opportunities and the suggested plans. The book concludes that an analytical decision-making process should be used to assess a health technology on the basis of its performance. It stresses the importance of updating this analytical system frequently.