Depression is disabling chronic mental illness that prevents a person from functioning normally. The structural setting of depressive disorder requires the distribution of individual symptoms on the five following key - dimensions : a) emotional / experiential, b) behavioral, c) physical, cognitive, and e) functional. Most likely, depression is caused by a combination of genetic, biological, environmental, and psychological factors. The most common treatment options are medication and psychotherapy. Taken for granted that depression can be effectively treated, early screening and treatment are imperative.