This paper considers whether emerging wearable computing technologies could and should be applied to reducing older people's fear of crime. The paper begins by exploring the sociological and criminological literature, which debates why older people are most likely to fear crime, even though they are least likely to be victims. It goes on to report findings from ethnographic studies of key care and social service professionals in an English city. This field work reflects the ways in which assistive technologies for older people can function as signs of vulnerability, and also reports the uses of relatively simple information and communication technologies in providing critical backup and reassurance for elderly users. The fear of crime is then considered as an information problem centring on three questions: what's going on, what can I do about it and can I get help? Possible applications of emerging wearable surveillance technologies are then explored through a design concept called the Cambadge. This is a wearable, wireless webcam for older people to broadcast video and audio data to police or community Web sites. This concept is situated with reference to a company developing a similar technology and to related fields. It is argued that the design problems of such surveillance technology are inherently political. The case is made with reference to the history and philosophy of surveillance and the massive demographic shifts of the ageing population. It is argued that utopian visions of the uses of such technology under-theorise power and accountability. The paper concludes that technological innovations will not adequately address older people's fear of crime without accompanying social and cultural change.