Monitoring a patient during and after a surgical procedure is one of the prime responsibilities of the anesthesiologist, and it is hugely important because of the precarious and critical nature of the anesthetized state. This issue brings the anesthesiologist up to date on the most important recent innovations and changes in monitoring techniques and technologies. One of the key topics that has received much attention recently is awareness monitoring, which is vital to ensuring the patients comfort and protection throughout a surgical procedure. Monitoring coagulation, temperature, arterial and central venous pressure, perfusion, the central nervous system, and the spinal cord, as well as renal, hepatic, and endocrine function are all covered. The newest technologies are assessed. TEE monitoring is addressed for both cardiac function and the hemodynamically unstable patient. This vital issue equips the anesthesiologist with the newest information to monitor patients with great care and precision in order to diagnose and treat immediately any medical problems that may arise during surgery or the recovery period.