Following networks of mothers in London and Paris, the author profiles the narratives of women who breastfeed their children to full term, typically a period of several years, as part of an 'attachment parenting' philosophy. These mothers talk about their decision to continue breastfeeding as 'the natural thing to do': 'evolutionarily appropriate', 'scientifically best' and 'what feels right in their hearts'. Through a theoretical focus on knowledge claims and accountability, the author frames these accounts within a wider context of 'intensive parenting', arguing that parenting practices - infant feeding in particular - have become a highly moralized affair for mothers, practices which they feel are a critical aspect of their 'identity work'. The book investigates why, how and with what implications some of these mothers describe themselves as 'militant lactivists' and reflects on wider parenting culture in the UK and France. Discussing gender, feminism and activism, this study contributes to kinship and family studies by exploring how relatedness is enacted in conjunction to constructions of the self.