The International Early Learning and Child Well-being Study (IELS) 2025 was a collaborative effort between participating jurisdictions, the OECD Secretariat, and the international Consortium. The study and this report were guided by Andreas Schleicher and Yuri Belfali. Responsibility for the implementation of the study rested with Rowena Phair until 2023 and with Claudia Tamassia, thereafter, supported by a team that included Nathaniel Reinertsen and Marco Paccangella.
Carlos González-Sancho was the lead author of the report and related dissemination products, with support from Nathaniel Reinertsen, Mila Staneva (Annex A) and Elizabeth Shuey and Roland Tusz (jurisdiction notes). François Keslair provided statistical and analytical support. Elizabeth Shuey, Stéphanie Jamet and Hannah Ulferts provided valuable feedback on draft chapters, while Marco Paccagnella and Francesco Avvisati offered technical advice. Administrative support was provided by Sabrina Leonarduzzi while communications support was provided by Eda Cabbar, Duncan Crawford, Sophie Limoges, Rachel Linden and Anna Wahlgren. Chapters 1 and 2 of this report draw on the Assessment Framework prepared by the Australian Council for Educational Research (ACER)/International Consortium.
The international Consortium was led by ACER and included also the International Association for the Evaluation of Educational Achievement (IEA) and cApStAn. It was responsible for developing the assessment instruments, guiding implementation, preparing the underlying data, and supporting countries throughout implementation. The Consortium operated under the direction of Maurice Walker (International Project Director, ACER), supported by Dan Cloney (Co-Deputy Director, ACER) and Clara Beyer (Co-Deputy Director, IEA).
To help ensure the rigour and validity of the study, the design and implementation of IELS 2025 were guided and supported by a Technical Expert Group (TEG), chaired by Iram Siraj.
This volume also benefited from reviews by teams from participating jurisdictions, including members of the Steering Group and National Project Managers. Their contributions to the report are gratefully acknowledged. A complete list of contributors from the OECD Secretariat, the international Consortium, the TEG and participating jurisdictions can be found in Annex C.