Mark Harold Greenberg, MD, received his medical degree from Northwestern University Medical School in Chicago, and completed his internship and residency at Northwestern Memorial Hospital and was a teaching attending physician at Northwestern Memorial Hospital, also in Chicago. He later completed a rheumatology fellowship at Albert Einstein-Montefiore Medical Center in New York City. He was in private practice in rheumatology in Florida for 31 years before joining the Division of Rheumatology.