The affective spectrum is a grouping of related psychiatric and medical disorders which may accompany bipolar, unipolar, and schizoaffective disorders at statistically higher rates than would normally be expected. These disorders are identified by a common positive response to the same types of pharmacologic treatments. They also aggregate strongly in families and may therefore share common heritable underlying physiologic anomalies. In this book, the authors discuss the epidemiology, signs and symptoms, and prognoses of affective disorders. Topics include psychotic features in bipolar disorder; the risk of suicide behaviours in affective disorders; the social impact of major affective disorders; and gender differences in depressive prevalence in response to psychosocial issues.