Anxiety disorders are thought to be one of the most common psychiatric diagnoses in children/adolescents. Chronic medical illness is a significant risk factor for the development of an anxiety disorder, and the prevalence rate of anxiety disorders among youths with chronic medical illnesses is higher compared to their healthy counterparts. Anxiety disorders may develop secondary to predisposing biological mechanisms related to a child's specific medical illness, as a response to being ill or in the hospital, a threatening environment, as a result of other genetic and psychological factors, or as a combination of all these factors. Additionally, exposure to physical pain early in one's life and/or frequent painful medical procedures are correlated with fear and anxiety during subsequent procedures and treatments, and may lead to medical nonadherence and other comorbidities. Anxiety disorders can have serious consequences in children/adolescents with chronic and/or life-limiting medical illnesses. Therefore, proper identification and treatment of anxiety disorders is necessary and may improve not only psychiatric symptoms but also physical symptoms. Behavioral and cognitive methods as well as psychotropic medications are used to treat anxiety disorders in pediatric patients. We will review current treatments for anxiety in children/adolescents with medical illnesses and propose future research directions. Depression and Anxiety 28:40-49, 2011.