This chapter of the Early Childhood Systems Building Resource Guide (SBRG) introduces equity in early childhood systems. In the chapter, equity is defined and examined within the context of state and federal early childhood systems. Equity is also examined using dimensions of capacity building from the Early Childhood Systems Building Resource Guide: Capacity Building Self-Assessment and examples from across the country are provided to illustrate each dimension. Finally, resources to delve deeper into this important topic are offered along with definitions of common terms. (author abstract)