This article draws on the articulation of a value for reflexivity that has accumulated within qualitative methods debates in the past decade. It demonstrates how reflexivity is interwoven with the concept of ethical mindfulness. The argument has developed from a consideration of the ethical dilemmas that were a salient aspect of an ongoing research relationship with children and young people during an unusually long longitudinal study, undertaken from the time the 10 participants were aged three to seventeen. The study explores the ongoing creation of a personal self during this time and draws on a range of ethnographic methods. The author focuses on two aspects of the "ethics in practice" that imbued her research relationships: the gaining and maintaining of consent, and the matching of methods to children's interests. The author makes a series of recommendations about how to "do" reflexivity, incorporating a set of guidelines for informed consent with children. The author concludes that reflexivity and ethical mindfulness are interdependent concepts, an understanding that is particularly valuable for child-focused researchers.