The Starting Strong Teaching and Learning International Survey 2018 is an international survey of staff and centre leaders working in early childhood education and care (ECEC), administered in ECEC centres belonging to ISCED Level 0.2, and, as an option, centres providing services for children under the age of 3. The Conceptual Framework provides an integrated theoretical and analytical underpinning to the survey that articulates its research foci and links to existing knowledge and evidence and policy questions. The key themes include those mainly concerned with: ECEC staff-child interaction (process quality of staff-child interaction and monitoring and assessment of children’s development, well-being and learning); ECEC centre characteristics (structural quality characteristics, pedagogical and administrative leadership, climate, and stakeholder relations); ECEC leader and staff characteristics (background and initial preparation, professional development, well-being, professional beliefs about children’s development, well-being and learning, and self-efficacy); and the cross-cutting theme of equity and diversity in the child group.