Dr. John Koo is a professor of dermatology at the University of California at San Francisco (UCSF). He received his medical degree from Harvard Medical School. He is board certified in both psychiatry and dermatology.

Dr. Koo has authored or coauthored more than 300 peer reviewed articles and books published in journals such as the Journal of the American Academy of Dermatology and other journals. Currently, Dr. Koo is founding editor of Journal of Psoriasis and Psoriatic Arthritis.

Dr. Koo has been listed in Best Doctors in America continuously for several decades. He is the recipient of 2014 American Skin Association (ASA) Annual Research Award, Best Speaker Award at Fall Clinical Symposium and Best Mentor Award at his home institution of UCSF Medical Center. Lastly, he is the 3rd recipient of Lifetime Achievement Award by National Psoriasis Foundation.

Dr. Koo serves as a medical advisory board member for the National Psoriasis Foundation and chairs the Psoriasis Expert Resource Group (PERG), a joint task force of the American Academy of Dermatology and the National Psoriasis Foundation. He is a founding member of the Association for Psychocutaneous Medicine of North America. With his extensive knowledge and expertise, Dr. Koo is frequently invited to lecture at national and international conferences.

Lastly, in the 2023 Newsweek survey of thousands of dermatologists across USA, Dr. Koo was voted as the 6th most prominent medical dermatologist out of almost 20,000 dermatologists in the entire USA.