In the haemophilic patient, development of antibodies that inhibit the function of the missing coagulation factor causes several delicate problems. Most importantly, antibodies will block the function of the specific coagulation factor, and often the antibody activity is so fierce that effective substitution therapy is outruled. In consequence, alternative measures must be adopted to control bleeding. Amongst those most commonly employed, like factor IX concentrates, activated prothrombin complex concentrates, and factor VIII of porcine origin, a new recombinant activated factor VII molecule has been evaluated clinically for some years with promising results. The aim of the present paper was to present a series of patients suffering from haemophilia A or B in whom inhibitors have complicated the clinical picture, and in whom a surgical procedure was indicated. As part of a compassionate use program devised by the producer of this genetically engineered factor VIla, 12 patients underwent life-saving or essential surgery where the recombinant factor VIla product was used to promote haemostasis in 13 surgical procedures. Due to a short in vivo half-life of activated factor VIla, frequent administration was scheduled, injecting factor VIla every 2-3 h for up to 2 days after which dosage intervals were prolonged. In one case, a global evaluation of the end treatment result was not reported, but in all of the other 12 cases the end result were considered excellent (n = 11) or efficient (n = 1). In none of the cases was other types of coagulation factor treatment modalities necessary. In conclusion, recombinant factor VIla seems a tempting alternative to traditional treatment of the haemophilic patient with inhibitors, in whom surgery is called for. With other types of haemostatic agents, surgery in haemophilic inhibitor patients has only been studied rarely, and operations have generally been restricted to life-threatening situations.