Early childhood education (ECE), also known as nursery education, is a branch of education theory that relates to the teaching of children (formally and informally) from birth up to the age of eight. Traditionally, this is up to the equivalent of third grade. ECE is described as an important period in child development.

ECE emerged as a field of study during the Enlightenment, particularly in European countries with high literacy rates. It continued to grow through the nineteenth century as universal primary education became a norm in the Western world. In recent years, early childhood education has become a prevalent public policy issue, as funding for preschool and pre-K is debated by municipal, state, and federal lawmakers. Governing entities are also debating the central focus of early childhood education with debate on developmental appropriate play versus strong academic preparation curriculum in reading, writing, and math. The global priority placed on early childhood education is underscored with targets of the United Nations Sustainable Development Goal 4. As of 2023^[update], however, "only around 4 in 10 children aged 3 and 4 attend early childhood education" around the world. Furthermore, levels of participation vary widely by region with, "around 2 in 3 children in Latin American and the Caribbean attending ECE compared to just under half of children in South Asia and only 1 in 4 in sub-Saharan Africa".

ECE is also a professional designation earned through a post-secondary education program. For example, in Ontario, Canada, the designations ECE (Early Childhood Educator) and RECE (Registered Early Childhood Educator) may only be used by registered members of the College of Early Childhood Educators, which is made up of accredited child care professionals who are held accountable to the College's standards of practice.

Research shows that early-childhood education has substantial positive short- and long-term effects on the children who attend such education, and that the costs are dwarfed by societal gains of the education programs.

According to the OECD, investing in high-quality early childhood education and care (ECEC) is a cost-effective way to significantly enhance children’s cognitive, social and emotional development. Skills acquired at an early age provide the foundation for later learning and increase the effectiveness of subsequent educational investments.

The Developmental Interaction Approach is based on the theories of Jean Piaget, Erik Erikson, John Dewey, and Lucy Sprague Mitchell. The approach focuses on learning through discovery. Jean Jacques Rousseau recommended that teachers should exploit individual children's interests to make sure each child obtains the information most essential to his personal and individual development. The five developmental domains of childhood development include:

To meet those developmental domains, a child has a set of needs that must be met for learning. Maslow's hierarchy of needs showcases the different levels of needs that must be met the chart to the right showcases these needs.

Friedrich Froebel was a German Educator that believed in the idea of children learning through play. Specifically, he said, "play is the highest expression of human development in childhood, for it alone is the free expression of what is in the child's soul." Froebel believed that teachers should act as a facilitators and supporters for the students's play, rather than an authoritative, disciplinary figure. He created educational open-ended toys that he called "gifts" and "occupations" that were designed to encourage self expression and initiation.