This guide is intended to serve as a reference tool for planning, designing and building early childhood spaces that are safe, healthy, nurturing, developmentally appropriate and aesthetically pleasing for the children and adults who use them. The physical environments in which young children spend their days learning, playing and socially interacting contribute significantly to their developmental growth. Brain development research shows that the first three years of life are a time of rapid cognitive and physical development. Understanding the developmental behaviors of young children and the programmatic and operational needs of early childhood professionals are essential to designing, developing and financing sustainable facilities that will support quality child care programs. (author abstract)