Advances in diagnostic evaluation, including autoantibody assessment, are reviewed, and the diagnostic features of euthyroid TED are also discussed. All relevant aspects of treatment are covered, from the use of radioactive iodine, long-term medical therapy, and surgical thyroidectomy through to the treatment of active TED by steroids and novel biologics and the role of minimally invasive surgery. Numerous supporting images are included, and helpful checklists will aid the practitioner in treatment decision making.