Results from clinical trials of glycoprotein IIb/IIIa(GPIIb/IIIa) inhibitors during the past decade have established their current role in the treatment of non-ST-segment elevation acute coronary syndrome and in percutaneous coronary interventions. However, there are still unanswered questions on optimal use of GPIIb/IIIa inhibitors. Moreover, as new concomitant or alternative medications become available, the role of GPIIb/IIIa inhibitors must be reconsidered. This review discusses, in the light of clinical trials recently presented, what we know, what we are learning, and what we still need to learn.