It is often assumed that there is broad public support for strong life extension research (i.e. research aimed at the dramatic extension of human life beyond the current maximum), and that there would be a near universal interest in using any life extending technologies that this research may produce. In this paper we report the opinions of researchers in ageing on the controversial promise of life extension, and compare these views. This paper describes the professional attitudes, personal interest and concerns expressed by Australian and international researchers in ageing (n = 14) as expressed during semi-structured, in-depth interviews. Researchers held varying opinions about the possibility of significantly extending human life. Some saw a limit to the extension of human life, while others did not. Some felt that research into the fundamental ageing process was a priority; others did not. Researchers tended to weigh up the potential risks and benefits of life extension with most expressing a personal interest in life extension that was contingent on the technology providing a good quality of life. Some participants were not interested in the prospect of life extension for personal reasons, because they felt the potential risks outweighed the potential benefits, or because life extension raised issues of justice and equity.