The momentum behind high-quality, voluntary pre-kindergarten is growing dramatically across the country--in families, in communities, and in the halls of academia and government. Thanks to this strong wave of support, state spending on pre-k increased from $2.4 billion to $4.2 billion nationwide between 2002 and 2007. This investment is built upon a solid research base, which shows that quality pre-k makes the most of children's crucial early brain development, meets their social and educational needs, and gives them a strong foundation for school and life. The potential impacts of pre-k have been the subject of many benefit-cost (B/C) analyses and other economic studies. However, to make the best use of this growing body of research, stakeholders must be able to cite those studies that best address the particular questions and issues that arise in their states. The purpose of this report is two fold. First, it provides readers with a "one-stop shop" for the most current and relevant economic-impact studies of pre-k. Second, it highlights the key arguments made by these studies as well as other factors to consider in their use to help readers more strategically choose those studies that speak directly and appropriately to the interests and concerns of their audience. Individual sections contain notes. (Contains 2 tables, 1 figure and 9 resources.)