Glanzmann thrombasthenia (GT) is an autosomal recessive bleeding disorder characterized by deficient or dysfunctional glycoprotein (GP) IIb/IIIa compexes. The hallmark of the disease is impaired platelet aggregation stemming from defective fibrinogen binding to GPIIb/IIIa. Based on deciphering the abnormality in GT a monoclonal antibody, peptides and peptidominetic agents, all interfering with fibrinogen binding to GPIIb/III complex, have been developed and successfully used to create a transient thrombasthenia-like state in patients with imminent arterial thrombosis. Currently, the main benefit afforded by these agents has been observed in patients undergoing percutaneous coronary interventions who are at high risk of thrombosis but more indications for their use are evolving.