ISOTIS addresses the nature, causes and impact of early emerging social and educational inequalities in the context of socioeconomic, cultural and institutional processes. The aim is to contribute to effective policy and practice development to combat inequalities. Quasi-panels and pooled longitudinal datasets will be used to examine the variation in early educational gaps and developmental trajectories across countries, systems and time. To disentangle the complex interactions between characteristics of systems and target groups, ISOTIS will study significant immigrant, indigenous ethnic-cultural and low-income native groups, associated with persistent educational disadvantages. ISOTIS will examine current resources, experiences, aspirations, needs and well-being of children and parents in these groups in the context of acculturation and integration, and in relation to local and national policies. ISOTIS aims to contribute to effective policy and practice development by generating recommendations and concrete tools for (1) supporting disadvantaged families and communities in using their own cultural and linguistic resources to create safe and stimulating home environments for their children; for (2) creating effective and inclusive pedagogies in early childhood education and care centres and primary schools; for (3) professionalization of staff, centres and schools to improve quality and inclusiveness; for (4) establishing inter-agency coordination of support services to children and families; and for (5) developing policies to combat educational inequalities. ISOTIS will develop inter-linked programmes for parents, classrooms and professionals using Virtual Learning Environments for working in linguistically diverse contexts. All this work together is expected to support the education practice and policy field in Europe in meeting the challenges of reducing social and educational inequalities.