Many Philosophy for Children (P4C) practitioners in different parts of the world have recognized the need for contextually relevant texts and created new stories and other materials to use as starting points for inquiry, some more sophisticated and comprehensive than others. P4C (Philosophy for Children) stands for the name of the comprehensive school curriculum and pedagogy which was designed to guide and support teachers trained to introduce philosophy lessons to their pupils. The acronym PwC (Philosophy with Children) refers to any form of philosophy practiced with children. P4wC (Philosophy for or with Children) emerged subsequently to cover a range of philosophical practices with children that includes similar community of inquiry practices with adults. This article addresses two issues: the boundaries of the practice of Philosophy for or with Children (P4wC) and the boundaries separating the disciplines that inform the P4wC movement -- in particular, the boundaries between philosophy and the disciplines of education and psychology. The author argues that the movement would benefit from becoming somewhat less open to a wide range of interpretations of practice and somewhat more open to insights from related disciplines.