Daniel J. Siegel is an American psychiatrist and clinical professor of psychiatry at the UCLA School of Medicine. He is known for his work in the field of interpersonal neurobiology, which explores how relationships and the brain interact to shape human experience. Siegel has authored several influential books, including The Mindful Therapist and The Whole-Brain Child, which focus on integrating mindfulness and neuroscience into therapeutic practices. In addition to his academic work, Siegel is a co-founder of the Mindsight Institute, which offers training and resources for professionals in mental health. He emphasizes the importance of understanding the mind and fostering emotional well-being through awareness and connection.