In this paper we argue that while individual private interests such as autonomy and the need for a medical procedure or treatment are important in the provision and delivery of health care and the utilization of biotechnologies, these concepts need to be balanced with other interests such that in certain situations they do not take priority. We use as an example a particular developing biotechnology, xenotransplantation, to suggest that interest in the health of the public is such that this biotechnology (...) should not be permitted to move to the clinical trial stage because of the particular risk of harm it poses to the potential xeno-recipient, their close contacts and the wider population. This is despite the interest of those in need of a transplant in allowing such clinical trials to proceed. We derive support for our position from John Stuart Mill's harm principle. (shrink)