Do charter schools draw good teachers from traditional, mainstream public schools? Using a panel dataset of all North Carolina public school teachers from 1997-2007, this research paper finds nuanced patterns of teacher quality flowing into charter schools. High rates of inexperienced and uncertified teachers moved to charter schools, but among certified teachers changing schools, the on-paper qualifications of charter movers were better or no different than the qualifications of teachers moving to comparable mainstream schools. Estimated measures of classroom performance for a subset of grade 3 - 5 teachers show that charter movers were more effective in math and reading instruction, relative to other mobile teachers. Charter movers compared less favorably, however, to non-mobile teachers and colleagues within their sending schools. The distribution of classroom performance among future charter teachers, adjusted for sampling error, was significantly lower than the distribution for exclusively mainstream teachers.