The French law on organ harvesting in brain dead patients allows this to be done without the family's consent, but prescribes to inform the relatives. Despite this, most teams do not harvest organs if the family is strongly opposed to the procedure. Information given to the relatives is therefore a very important point in the management of the donor. This prospective multicentre enquiry was designed to assess the conditions in which relatives were informed, and to determine the criteria which improve the rate of consent for the donation. After such information had been given, a questionnaire was filled in and sent to France-Transplant. Two hundred and seven interviews were analysed over an 18-month period. In two thirds of cases, the relatives were interviewed less than three hours after the diagnosis of brain death had been made. A written information sheet was used in only one third of interviews. Information was given by telephone in 11 % of cases. Organ donation was accepted, on average, in 74 % of cases. This ratio, which did not depend on the hospital, increased with the age of the donor : 66 % for donors aged less than 18 years to 86 % for those more than 50 years old. The aetiology of brain death was not a factor determining acceptance of the donation. The main factor was the conditions of interview : acceptance rate was the highest when there was a one hour delay between giving the information on the donor's brain death and that concerning organ donation. Asking the relatives to take part in making the decision, or allowing for time for thought, were not responsible for decreased acceptance rates. Finally, neither the interviewer's professionnal qualification nor his sex or age were significant factors of consent to donation, but experience and quality of communication were essential. Some guidelines are provided to improve the communication when giving this kind of information.