Disease of the endocrine system is common and can present as either the primary reason for surgery or as a significant co-morbidity in a patient admitted for an unrelated surgical procedure. The endocrine organs have an essential role in governing physiology via the hormones they produce; raised or lowered levels of these hormones lead to physiological disruption and illness. Surgeons should understand how to manage such patients in the perioperative period and also how to monitor for, and treat, complications arising. Unrecognized and uncontrolled endocrine disease can have an impact on the outcome from surgery. This article will cover the perioperative management of the common endocrine disorders including diabetes, thyroid disease and disease of the adrenal glands. It will also cover the emergency management of the endocrine crises that may arise.