Informed consent is a concept which attempts to capture and convey what is regarded as the appropriate relationship between researcher and research participant. Definitions have traditionally emphasised respect for autonomy and the right to self-determination of the individual. However, the meaning of informed consent and the values on which it is based are grounded in society and the practicalities of social relationships. As society changes, so too do the meaning and practice of informed consent. In this paper, we trace the ways in which the meaning and practice of informed consent has changed over the last 35 years with reference to four qualitative studies of parenting and children in the UK which we have undertaken at different points in our research careers. We focus in particular on the shifting boundaries between the professional and personal, and changing expressions of agency and power in a context of heightened perceptions of risk in everyday life. We also discuss developments in information and communication technologies as a factor in changing both the formal requirements for and the situated practicalities of obtaining informed consent. We conclude by considering the implications for informed consent of both increasing bureaucratic regulation and increasingly sophisticated information and communication technologies and suggest strategies for rethinking and managing 'consent' in qualitative research practice.