Abstract: Today, 25 states and the District of Columbia restrict the growth of charter schools in some fashion, including restrictions on individual authorizers or limits on the number of charter schools allowed to open. Few of the restrictions address the issue of charter school quality, but rather bluntly limit public schooling options and choices for families. The author calls for "smart charter school caps" that focus on growth and quality help states expand high-quality schooling options for underserved students.