Technological advances are bringing new light to privacy issues and changing the reasons for why privacy is important. These advances have changed not only the kind of personal data that is available to be collected, but also how that personal data can be used by those who have access to it. We are particularly concerned with how information about personal attributes inferred from collected data (such as online behaviour), can be used to tailor messages and services to specific individuals or groups. This kind of ‘personalised targeting’ has the potential to influence individuals’ perceptions, attitudes, and choices in unprecedented ways. In this paper, we argue that because it is becoming easier for companies to use collected data for influence, threats to privacy are increasingly also threats to personal autonomy—an individual’s ability to reflect on and decide freely about their values, actions, and behaviour, and to act on those choices.2 While increasing attention is directed to the ethics of how personal data is collected, we make the case that a new ethics of privacy needs to also think more rigorously about how personal data may be used, and its potential impact on personal autonomy. We begin by briefly reviewing existing work on the value of privacy and its link to autonomy, before outlining how recent technological advances are changing this relationship by changing the ways that personal information can be used to influence behaviour. We introduce the idea of ‘personalised targeting’, and discuss its implications for autonomy, before finally presenting some considerations for determining when this kind of targeting is acceptable and when it is not. Finally, we conclude with some practical implications for thinking about the ethics of how data is used.