We are pleased to publish this issue of the Children’s Research Digest on the theme of “Extending the learning from the Prevention and Early Intervention Initiative”. This special edition of the Digest reports on new research that has been generated by the Prevention and Early Intervention Research Initiative (PEI-RI) research grants scheme at the Children's Research Network. In total, sixteen grants were awarded in 2017 and 2018 to support new analysis of evaluation data from Atlantic Philanthropies' investment in the Prevention and Early Intervention Initiative between 2004 and 2016.

The PEI Research Grants were awarded to teams from a number of academic institutions across the island of Ireland, working in a broad range of disciplinary areas. This is evident in the variation of articles presented in this edition of the Digest. Many of these projects were still in progress at the time of publication, and articles report on work in progress towards a variety of peer reviewed dissemination activities.

The PEI-RI research grants scheme had an explicit focus on capacity building for early career researchers under the mentorship of senior colleagues, and this edition presents the results of a number of these collaborations. In addition three awards were made to 'senior scholars' in prevention and early intervention to engage and disseminate the PEII data internationally, for example through a comparative analysis of a PEII data set with an international data set. 

This special edition has been published in December 2018 to mark the conclusion of the Prevention and Early Intervention Research Initiative project at the Children's Research Centre. 

We would like to thank all authors and the reviewers for their contributions to this issue. Special thanks are also due to all who helped with proof reading and to AAD for providing the design and layout. We would also like to thank Suzanne Guerin for acting as Guest Editor, and Atlantic Philanthropies for their support of the Prevention and Early Intervention Research Initiative at the Network.