This white paper explores the concepts of child care supply and demand from both the perspectives of 1) parental choices and decisions made related to finding quality child care, and 2) state- and community-level approaches to documenting and addressing child care deserts. First, we highlight the themes around parent child care journeys that emerged from a series of focus groups with parents from vulnerable populations. Next, we provide an overview of several key informant interviews conducted with selected state- and community-level studies of child care deserts. For each community, we document motivations for studying deserts, the process they undertook to collect data, the reports and/or online tools they developed, how data was used to influence policy or community change, and where readers can go for more information. The report gleans lessons learned from these efforts. We also included several snapshots of supply and demand work of other states and communities throughout this paper. Finally, we propose policy solutions to improve access to quality child care for vulnerable populations. (author abstract)