Donor-advised funds (DAFs) are changing the mode of philanthropy in the United States. The lack of research on DAFs leaves nonprofit managers and policymakers with little empirical evidence or theoretical framework. The purpose of this dissertation is to provide scholarly research about why people use DAFs, how they function within the nonprofit economy, and what public policies may most effectively address public concerns. To this end, the dissertation is a combination of three peer-reviewed scholarly articles covering these topics. The first article tests behavioral economic concepts relating to charitable giving that help to explain why people use DAFs. The results showed that lower prices of giving lead to increases in charitable giving amounts and that increases in agency lead to higher participation rates in giving. The second article addresses how money flows through DAFs to other charities, and how this grantmaking is affected by macroeconomic factors. The study uses a panel data set of about one thousand DAF sponsors over a ten-year period, and merges this data with four macroeconomic factors. The findings suggest that money flows relatively quickly through DAFs to other nonprofits, and that giving out of DAFs is more resilient to recession economies than other forms of charitable giving. The third article reviews the public policy debates around donor-advised funds and makes public policy recommendations. The paper starts by reviewing the three major policy issues with DAFs: 1) the timing of donations and tax deductions, 2) transparency issues, and 3) the costs to the federal government. After analyzing current proposals within a historical context, the paper makes recommendations designed for the best interest of the nonprofit sector as a whole. The dissertation as a whole represents a seminal effort to conduct empirical research on donor-advised funds to better understand them and provide a theoretical framework for public policy.