Clinical trials provide average effects of interventions but are not powered to identify differences in subgroup responses. African-Americans have been under-represented in most previous trials in patients with heart failure. Furthermore, physiologic differences have been demonstrated between African-Americans and whites in the mechanisms and response to therapy in hypertension. Review of previous heart failure trials reveals that African-Americans exhibit less benefit than whites from ACE inhibitors, angiotensin receptor blockers, and at least one b-blocker. In contrast, black patients experienced a greater benefit than white patients from the combination of nitrate and hydralazine. These data emphasize the need for trials in black patients to identify effective therapy. The first such trial, African-American Heart Failure Trial, is currently underway.