We describe the management of a young boy with mild haemophilia A and a massive iliac pseudotumour with a multi modality approach involving factor replacement, radiation therapy, embolization and surgery. The patient was initially treated with recombinant factor VIII and radiation therapy. Because of inadequate response and worsening of bony erosion, the patient had a preoperative embolization followed by surgical excision. The surgical procedure was associated with minimal blood loss and the patient had a relatively smooth postoperative course with no physical morbidity. This case illustrates successful aggressive management of a large, proximally located pelvic pseudotumour, which resulted in an excellent outcome despite the need for a normally morbid operation.