The purpose of this document is to provide a reference guide for groups working toward achieving optimal and equitable health outcomes for young children and their families to identify, select, and track data indicators that can inform and advance their efforts. Indicators are defined here as measurable information used to assess or approximate (i.e., indicate) conditions such as child health and well-being. This guide is based on an environmental scan of datasets, tools, and toolkits related to early childhood, health, education, economic factors, and other indicators. Information on each resource was pulled directly from its website, including summary information, types of data, and suggestions for using it. A subset of datasets and tools were selected to feature in this guide, including state and/or community measures that were curated based on the target audience. (author abstract)