Dr. Brigitte Kieffer (born 26 February 1958) is a French molecular neurobiologist known for her research of opiate receptors. Her areas of expertise include: molecular psychiatry, addiction, mood disorders, pain, and developmental disorders. Kieffer has international reputation in the field of opiate receptors, and has paved the way for better understanding of brain mechanisms involved in pain, mental illness, and drug addiction. She continues to pursue research and directs a team of over 300 people. Her discoveries have shed light on how substances like morphine or heroin can kill pain, and foster addiction.