Ketamine plays an important role in prehospital emergency medicine. Common indications are analgesia, sedation, and anesthesia. The application in those established areas is expanding even further, as traditional contraindications, like intracranial or intraocular hypertension, have been revised. In addition, novel indications for ketamine with potential for use in the field of prehospital emergency medicine are emerging. These include bronchodilation in severe asthma, termination of seizures, and the use of ketamine in certain intoxications. However, promising data from experimental studies or limited patient series must be confirmed in larger, high-quality trials. The results of high-quality trials will eventually inform prehospital emergency practitioners regarding the optimal use of ketamine, ultimately supporting improved patient outcomes.