Over the last decade, a growing consensus has developed that for our nation's students to succeed in twenty-first-century economic and civic life, high school graduation is no longer sufficient. Labor-market analyses have shown that high-wage positions increasingly require postsecondary education and training, and students must now graduate from high school prepared to succeed in college and career. In response to these changes in the economy and labor force, policies are being adopted across the country, including the Common Core State Standards and accompanying assessments. These standards, to be implemented in 2014 in most states, codify the new skills required for students to be proficient in mathematics and English language arts. The codification of these broad college and career aspirations into policy opens up the possibility of a new era of equity, in which all students, including those who have historically been poorly served by the public education system, have the same access to and preparation for higher education that affluent families take for granted. At the same time, the new requirements present a colossal challenge to school systems. Not only must they get better at identifying which students are struggling, they must figure out how to use that information to support those students. Three years ago, the Annenberg Institute for School Reform at Brown University (AISR) joined two other university-based partners--the John W. Gardner Center for Youth and Their Communities at Stanford University (Gardner Center) and the University of Chicago Consortium for Chicago School Research (CCSR)--and five urban sites, with support from the Bill & Melinda Gates Foundation, to address these challenges. The goal of the College Readiness Indicator Systems (CRIS) initiative was to develop a model for systems that would not only generate data for districts on whether each student was on track for college readiness, but would also tie those data to supports and interventions that would help keep students on track. The contributions to this issue of "Voices in Urban Education" reflect the lessons of three years of work on the CRIS project. Collectively, they frame the current understanding of college readiness and show how college readiness indicator systems are being infused into the day-to-day work and culture of the CRIS sites.