This article focusses on depression which the DSM-III classifies into 2 categories. Unipolar depressive illness occurs more commonly in women & has an average age of onset in the late thirties or early forties while bipolar or manic-depressive illness affects men & women equally & the average age ofonset is younger. Several aspects of depression are discussed. These include the frequency, etiology, & diagnosis of theillness. The authors also present a section on ways to deal with depression.