This paper offers an ethical framework for the development of robots as home companions that are intended to address the isolation and reduced physical functioning of frail older people with capacity, especially those living alone in a noninstitutional setting. Our ethical framework gives autonomy priority in a list of purposes served by assistive technology in general, and carebots in particular. It first introduces the notion of ''presence'' and draws a distinction between humanoid multi-function robots and nonhumanoid robots to suggest that the former provide a more sophisticated presence than the latter. It then looks at the difference between lower-tech assistive technological support for older people and its benefits, and contrasts these with what robots can offer. This provides some context for the ethical assessment of robotic assistive technology. We then consider what might need to be added to presence to produce care from a companion robot that deals with older people's reduced functioning and isolation. Finally, we outline and explain our ethical framework. We discuss how it combines sometimes conflicting values that the design of a carebot might incorporate, if informed by an analysis of the different roles that can be served by a companion robot.Keywords Robots Á Ethics Á Telecare Á Assistive technology Á Autonomy Á Nature of care Á ACCOMPANY What role might robots have in the future care at home of older people? That depends on the kind of robot and the aspects of ageing addressed. We argue that social robotsrepresented in our discussion by the Care-O-bot Ò -commendably integrate the functions of useful non-robotic telecare devices, and that they also have a claim to the potentially therapeutic property we call ''presence''. The relevant normative requirements that we discuss are mostly ethical, though they might also include value for money, and considerations about the range of physical environments in which the relevant technology can operate. The ethical framework we present in this paper was developed in the European Union-funded FP7 ACCOMPANY project, which has adapted the Care-O-bot Ò as a home companion for older people. ACCOMPANY scenarios primarily address the isolation and reduced physical functioning of some older people, especially those living alone in a non-institutional setting. Our ethical framework gives autonomy priority in a list of purposes served by assistive technology in general, and carebots in particular, for isolated and frail older people.The paper consists of four sections. In the first, the capacity of robots to be ''present'' to their users is introduced. We argue that presence is a necessary condition for being a companion robot but a far from sufficient condition of being a carer or even of being a care-robot in a substantial sense of 'care'. In the second section we describe relatively low tech assistive technology and its benefits, and contrast these with what a robot can offer. The possible ethical problems of carebot design are then considered, on the ...