School choice behavior provides critical information on how parents value and trade off different attributes of schools and neighborhoods. Researchers can harness this information to improve policy in a variety of ways. For example, city leaders can plan where to build and improve schools, how many and what type of charter schools to approve, and what restrictions to place on choice in order to maximize school quality, promote equal opportunity, and limit race and class segregation. Despite the fact that public school choice has been around for decades, the education marketplace has traditionally been fragmented and difficult for researchers to study. Few studies (Glazerman, 1998; Hastings, Kane, & Staiger, 2010) have been able to capitalize on school choice to gauge parent preferences. Recently, however, several cities around the country have begun unifying their school lottery and admissions processes, making it possible for the first time to apply statistical analysis in a systematic way and to start informing big policy decisions mentioned above. This panel presents results from three new studies on the cutting edge of school choice research, working with data from these new unified lotteries in Washington, DC, New Orleans, and New York City. The studies each seek to interpret market signals sent by families making important decisions about where to send their children for school.