Antiplatelet therapy with a P2Y12 inhibitor is a key component of treatment for patients with acute coronary syndromes undergoing percutaneous coronary intervention. Before the development of cangrelor (Kengreal, The Medicines Company, Parsippany, NJ), only oral P2Y12 inhibitors were available. Cangrelor is a reversible P2Y12 inhibitor that is administered as an intravenous infusion, and its quick onset and offset make it an appealing option for antiplatelet therapy, particularly for patients who are unable to take oral medications. Although cangrelor struggled to show benefit in early trials, the positive results of the CHAMPION PHOENIX trial led to its approval for use as an adjunct to percutaneous coronary intervention to reduce the risk of periprocedural myocardial infarction, repeat coronary revascularization, and stent thrombosis in patients who have not been treated with another P2Y12 inhibitor and are not being given a glycoprotein IIb/IIIa inhibitor. Cangrelor has also been evaluated as an option for bridging therapy in patients who must discontinue their oral P2Y12 inhibitor before coronary artery bypass grafting. This review of cangrelor will discuss its mechanism of action, its pharmacodynamics and pharmacokinetics, the clinical trial experience, and its potential place in therapy.