Duloxetine Versus Placebo in the Prevention of Relapse of Major Depressive Disorder

Inclusion Criteria: * Signed the informed consent * Meet criteria for major depressive disorder without psychotic features. * Have a level of understanding sufficient to provide informed consent and to communicate with the investigator and site personnel. * Have had at least one other major depressive episode prior to the one being experienced at study entry. * You are reliable and agree to keep all appointments for clinic visits, tests and procedures required by the protocol. Exclusion Criteria: * You have had treatment with a drug within the last 30 days that has not received regulatory approval at the time of study entry. * Any women who are pregnant or breast feeding. * If you have any serious medical illnesses other than major depressive disorder. * If you have previously participated in a clinical trial for duloxetine. * Any previous or current diagnosis of bipolar, schizophrenia, or other psychotic disorders.