Dr. Papagiannopoulos grew up near Chicago.  He attended St. Louis University, where he completed his Bachelor of Arts in Biology.  He then attended St. Louis University School of Medicine, where he completed his Doctorate of Medicine.  During his third year of medical school, he discovered his passion for psychiatry, and chose to pursue this specialty. 

He completed his residency in Adult Psychiatry at the Medical College of Wisconsin, in Milwaukee.  During this time, he came to appreciate the significance of early development, and how deeply it shapes our adult lives.  He then completed an additional 2-year fellowship in Child/Adolescent Psychiatry at the Medical College of Wisconsin.  He began his independent practice in Chicago. He then moved to New York City, which he now calls home.