The aim of this international study was to determine if 10 weeks of flexible-dose vardenafil therapy demonstrates superior efficacy compared to the dummy drug (placebo) in Erectile dysfunction subjects of a broad etiology when dosed 8 (+/-2) hours prior to sexual intercourse. In addition it should have been determined, if subjects with ED from a broad etiology can tolerate 10 weeks of flexible-dose vardenafil therapy when dosed 8(+/-2) hours prior to sexual intercourse.