Nationwide, one-third of children ages 5 and under have at least one parent who speaks a language other than English. These Dual Language Learners (DLLs) are an incredibly diverse and growing group of young children, and with the right support these preschoolers have the potential to develop as multilingual and multiliterate individuals. Yet detailed data on the number and characteristics of DLLs in early childhood education and care (ECEC) programs are rare, due to a lack of standardized policies and procedures for identifying them. This information is urgently needed to ensure these programs are responsive to DLLs' individual experiences and learning needs, and to support program improvements, professional development, resource allocation, and more. This report examines the extent to which federal agencies, states, and localities have procedures or guidance in place to identify DLLs in early childhood programs. Among the more advanced state and local efforts this analysis explores are those in California, Illinois, Minnesota, New York, and Pennsylvania. The report also includes a discussion of opportunities to advance more comprehensive DLL identification policies and practices. [For the companion issue brief, see ED614771.]