In 2008, the Welsh Assembly Government began the implementation of a new holistic play-based learning continuum for children aged three to seven called the Foundation Phase. Areas of learning replaced subjects and consequently pupils in Wales under the age of seven no longer study Physical Education in its traditional form. With growing recognition of the importance of physical literacy and the role that Physical Education plays in its development, a three-phase complementarity mixed methods study explored the impact of this new curriculum on pupils' physical literacy, finding that the Foundation Phase makes a positive contribution to the development of physical literacy. This paper reports on two phases of that study to examine what the Foundation Phase is and how it is enacted in schools that have been identified as showing good practice. Phase one used documentary analysis and semi-structured interviews to gain an in-depth analysis of the curriculum. Phase two used mixed methods to ascertain fidelity of curriculum implementation. Findings suggest that the schools in the study were implementing the Foundation Phase with fidelity to the original aims of the policy makers and as such pupils were independent, motivated active learners making good progress in the development of physical literacy.