Mood and anxiety disorders are prevalent in all countries and cultures, which becomes obvious when standardized diagnostic and evaluation techniques are utilized. It is estimated that ~450 million people worldwide suffer from psychiatric illness. In the United States alone, epidemiologic research has identified that tens of millions of Americans suffer from major depressive disorder (MDD) annually, with many of them being in the prime of their adult lives. In addition to medical, personal, and social costs, depression is also believed to have a significant impact on work productivity. Further epidemiologic research indicates that nearly half of all individuals meeting lifetime criteria for MDD also have met criteria for a comorbid anxiety disorder. With an average age of 16 years for the onset of any lifetime anxiety disorder, anxiety disorders appear to predispose affected individuals to a substantial lifetime risk for MDD. In order to improve outcomes in depression and anxiety disorders, clinicians must enhance the entire process of recognition, diagnosis, and treatment.