Charter schools, in their almost 30 years of existence, have moved from experimental schools to a mainstay of the nation’s educational landscape. Today charter schools, which are legal in all but six states, educate almost three and a half million students and substantial shares of students in several cities. This chapter reviews the growth of the charter sector and evidence of impact on student learning; considers existing evidence on how the hopes and fears surrounding charter schools have played out; and introduces the new issues and solutions that have emerged as this sector continues to evolve.