For years, only a handful of the highest achievers graduated from high school with college courses on their transcripts. However, as states strive to blur the line between high school graduation requirements and college expectations, such dual-enrollment courses are quickly becoming part of a broader strategy to help more students become college-ready. Over the past decade, much of the attention to dual enrollment has focused on expansion and funding. Some individual programs--and increasingly, states--are working, however, to ensure that quality goes along with the proliferation. They want courses that are challenging enough to warrant college credit and that can effectively prepare students for higher education. To help guide states' efforts, policy experts have identified promising practices, beginning with an intensive and sustained collaboration between high schools and colleges on course content, standards, and pedagogy.