Abstract
This article provides an overview of the ethical issues raised by the use of non-human primates (NHPs) in research involving scientific procedures which may cause pain, suffering, distress or lasting harm. It is not an exhaustive review of the literature and views on this subject, and it does not present any conclusions about the moral acceptability or otherwise of NHP research. Rather the aim has been to identify the ethical issues involved and to provide guidance on how these might be addressed, in particular by carefully examining the scientific rationale for NHP use, implementing fully the 3Rs principle of Russell and Burch (1959) and applying a robust "harm-benefit assessment" to research proposals involving NHPs.