The UN Convention on the Rights of the Child is acknowledged as a landmark in the development of children's rights. Article 3 makes the child's best interests a primary consideration in all actions concerning children and requires States Parties to ensure their care and protection. This volume, written by experts in children's rights from a range of jurisdictions, explores the implementation of Article 3 around the world. It opens with a contextual analysis of Article 3, before offering a critique of its implementation in various settings, including parenting, religion, domestic violence and baby switching. Amongst the themes that emerge are the challenges posed by the content of 'best interests', 'welfare' and 'well-being'; the priority to be accorded them; and the legal, socioeconomic and other obstacles to legislating for children's rights. This book is essential for all readers who interact with one of the Convention's most fundamental principles.