Our objective was to explore how prospective altruistic kidney donors construct their decision to donate. Using a qualitative design and biographical-narrative semi-structured interviews, we aimed to produce text for analysis on two levels: the social implications for subjectivity and practice and a tentative psychodynamic explanation of the participants’ psychological investment in the discourses they used. A total of six prospective altruistic kidney donors were interviewed. A psychosocial approach to the analysis was taken. In-depth discourse analysis integrated Foucauldian with psycho-discursive approaches and psychodynamic theory was applied to sections of text in which participants seemed to have particular emotional investment. Analysis generated three major discursive themes: other-oriented, rational and self-oriented discourses. The desire to donate was experienced as compelling by participants. Participants used discourses to position themselves as concerned with the needs of the recipient, to resist questioning and criticism, and to manage difficult feelings around mortality. Participants tended to reject personal motivations for altruistic donation, positioning relatives’ disapproval as selfish and illogical. These results suggest that the term ‘altruistic’ for living non-directed organ donation constrains available discourses, severely limiting what can be said, felt, thought and done by donors, clinicians and the public. A more useful approach would acknowledge potential psychological motives and gains for the donor.