Current evidence indicates that remission, the goal of treatment, is found in only about one-third of representative depressed outpatients treated for up to 14 weeks with an initial SSRI. In addition, even for those who do respond or remit, over one-third relapse in the subsequent 12 months. Combinations of antidepressants are used in practice at the second or subsequent steps when relapse occurs in the longer term, or, in some cases, even acutely as a first step when speed of effect is a clinical priority. Whether such combinations could potentially offer higher remission rates, lower attrition, or greater longer-term benefit if used as initial treatments as compared to monotherapy remains to be examined.