This issue of Anesthesiology Clinics, guest edited by Drs. Gabriella Iohom and Girish P. Joshi, focuses on Perioperative Monitoring. This is one of four issues each year selected by the series consulting editor, Dr. Lee Fleisher. Articles in this issue include, but are not limited to: Clinician monitoring, Ventilation monitoring, Measurement of pulmonary mechanics, Hemodynamic monitoring, Tissue perfusion monitoring, Neuromuscular blockade monitoring, Depth of anesthesia monitoring, Antinociception monitoring, Cerebral perfusion monitoring - Brain oxygen saturation monitoring, Coagulation, Ultrasound - the new stethoscope (POCUS), Mobile and Remote monitoring, smart phone use, AI, machine learning, deep learning, and closed loop devices and Telemedicine for anesthesiologists.?