Psychosocial distress is highly prevalent and diverse at all stages of cancer care. In the early 21st century, screening, assessment, and management of psychological distress in cancer patients are supported by a growing body of literature. Psychosocial care of cancer patients snow considered an essential component of quality cancer care by the Institute of Medicine. Increasing numbers of professionals from different disciplines are being trained in the United States and internationally to provide consultative services in support of the psychological care of cancer patients. This review article highlights the psychosocial distress experienced by cancer patients, featuring an overview of the assessment and management of psychological distress in the context of cancer as well as the common psychiatric disorders experienced by cancer patients at all stages of disease.