Mood disorder is a group of conditions in which an individual’s mood is affected. It manifests as mania or hypomania, depressive disorders and bipolar disorders. Some psychiatric syndromes or depressive disorders that feature less severe symptoms are cyclothymic disorder and dysthymic disorder. Mood disorders may also be triggered by substance use or may occur as a response to a medical condition. This may be an evolved mechanism of delimiting physical activities for assisting the individual to regain his health. A depressed mood can be a response to life’s occurrences, such as death of a child or spouse, divorce, loss of status, etc. Both therapy and medications can work to elevate mental health. Behavioral therapy, interpersonal therapy and cognitive behavioral therapy and drugs such as antidepressants, mood stabilizers, anticonvulsants and antipsychotics have potential benefits. This book explores all the important aspects of mood disorders in the present day scenario. It attempts to understand the varied mood disorders of modern society and their emotional and psychological implications. With state-of-the-art inputs by acclaimed experts of this field, this book targets students and professionals.