In comparison with other biotechnology substitutions, the adoption of recombinant Factor VIII (rFVIII) has been relatively slow. We sent a postal questionnaire to all Dutch haemophilia patients and haemophilia-treating physicians, to determine which factors predict whether a patient uses plasma-derived FVIII (pdFVIII) or rFVIII and to investigate patients' and doctors' opinions on both products. Fifty-six per cent of patients received rFVIII. This percentage varied widely between centres. Only one doctor would choose to use pdFVIII if he suffered from haemophilia A himself, and 74% would choose to use rFVIII. Younger patients, those not infected with the human immunodeficiency virus or hepatitis C, and those who did not have family members who used pdFVIII switched more often from pdFVIII to rFVIII. Patients who rated themselves as innovative, who had family members who used rFVIII, and those who were treated in a large haemophilia treatment centre were also more likely to have switched. For physicians and patients alike, the respondents generally did not see large differences between rFVIII and pdFVIII, except for the risk of infections and the knowledge of long-term effects (both larger for pdFVIII). Although haemophilia patients represent one of the most empowered patient groups, physicians appear to have been influential in choosing between pdFVIII and rFVIII.