Trauma are mental disorders that include the experience of a traumatic or very stressful event. Not everyone who experiences a great deal of stress or trauma will develop a mental health condition, but for those who do the cause can be traced directly to that situation as a causal factor. Trauma disorders must be treated or they can lead to serious complications ranging from problems at work to social isolation to depression and suicide.

Disorders related to trauma and stress were once classified as types of, or related to, anxiety disorders. That classification has changed, because although experiencing anxiety is common with trauma disorders, there may be other, more prominent emotional symptoms depending on the individual. Someone struggling with a trauma may experience depression, anger, aggression, or anhedonia more so than anxiety.