The American Psychiatric Association (APA) refers to disorders that have a disturbance in mood as their predominant feature as mood disorders. Depression is a mood disorder, which can be broken down into the following specific disorders: major depressive disorder, dysthymic disorder, bipolar disorder, cyclothymic disorder (a type of bipolar disorder), seasonal affective disorder (SAD), postpartum depression, mood disorder due to a general medical condition, and substance-induced mood disorders. In this chapter, you'll learn about different types of mood disorders, along with diagnosis and treatment options for each.