Core elements for Early and Effective Intervention (EEI) have been available since 2015. This updated version for June 2021 was commissioned by the Advancing Whole System Approach (WSA) Implementation Group and is intended to reflect current practice, taking into account new research, changes in practice and legislation since the original document was published. The aim of this framework is to clearly set out best practice for the effective delivery of EEI in order to enable services to meet these objectives.