Adolescent mental health problems have increased during the COVID-19 pandemic. Dr. Halldorsdottir describes why we need to be worried and what is needed to tackle the public health problem that is adolescent mental health.  Dr. Thorhildur Halldorsdottir is an assistant professor at Reykjavik University and a clinical child psychologist. She broadened her research to include behavioral genetics and epidemiology. Building on this multidisciplinary background, her research today focuses on understanding the connection between exposure to stress and trauma and psychiatric disorders.