Dr Krystal is a psychiatrist who cares for adults with all types of sleep disorders, with particular expertise in insomnia. He also treats patients who have mood and anxiety spectrum disorders in addition to sleep disorders. An internationally renowned expert on sleep and mood disorders, he has more than 25 years of experience in patient care and research. He is president of the Sleep Research Society and a member of the American Academy of Sleep Medicine, American Psychiatric Association and American College of Neuropsychopharmacology. He serves on the examination committee of the American Board of Sleep Medicine, which allows medical professionals to pursue certification in sleep medicine.