Emergence agitation (EA), which is also referred to as emergence delirium, can lead to clinically significant consequences. The mechanism of EA remains unclear. Proposed contributors to EA include age, male sex, type of surgery, emergency operation, use of inhalational anesthetics with low blood-gas partition coefficients, long duration of surgery, anticholinergics, premedication with benzodiazepines, voiding urgency, postoperative pain, and the presence of invasive devices. If pre- or intraoperative objective monitoring could predict the occurrence of agitation during emergence, this would help to reduce the adverse consequences of EA. Several tools are available for assessing EA; however, its incidence varies considerably according to the assessment tool and definition of EA used, due to the absence of standardized clinical research practice guidelines. Total intravenous anesthesia, propofol, μ-opioid agonists, N-methyl-D-aspartate receptor antagonists, nefopam, α2-adrenoreceptor agonists, regional analgesia, multimodal analgesia, parent-present induction, and preoperative education for surgery may contribute to prevention of EA. However, it is difficult to identify patients at high risk for EA and to properly apply EA prevention methods in various clinical situations, because both risk factors and preventive strategies often show inconsistent results depending on the methodology of the study and the patients assessed. This review discusses the most important research topics related to EA and directions for future research.