Unlike conventional antidepressants, rolipram stimulates both the presynaptic as well as the postsynaptic component of monoaminergic transmission. Several double-blind comparative trials are on the way to assess the clinical efficacy and safety of this novel compound. The present study was a randomized double-blind double-dummy comparison with imipramine in inpatients with major, "minor" and atypical depressions (DSM III). Results show no relevant differences between rolipram and imipramine regarding efficacy and safety.