This chapter explores variation in the expression and exercise of agency, in terms of what we know from the research literature to date. It considers some sources of difference that originate, primarily, in the child and then discuss differences in the child's context. In different cultures and in different settings within cultures child agency is enabled, restricted and channelled in different ways. Examination of such differences has already enhanced understanding of agency and its complexities, lending weight to Punch's hope that 'an engagement in cross-cultural dialogue between the minority and majority worlds could enhance our understanding of children's agency'. One of the main conclusions arrived at by researchers who note the diversity in expression of children's agency is that, to advance our understanding of child agency, the focus of research should not be on revealing instances of child agency but on examining and theorising how differences come about.