In the United States, early childhood programs inclusive of nature experiences for young children vary widely in terms of time spent outdoors; purpose of the program, approaches to use of the environment, curricular aims and support of young children's development. A commonality across many of these early childhood programs available in the United States is their focus on nature as a context for learning and play, some with an intentional approach to teaching about the environment, and, less commonly, to overtly engage with early childhood education for sustainability (ECEfS). The early childhood years are seen as a critically important time for learning, as well as for development of pro-environment behaviors and dispositions (Chawla & Derr, 2012), underscoring the importance of nature-based early learning.