In the continuing effort to raise the academic performance of public schools, improving teacher retention could be an important strategy for California. Keeping new teachers in the classroom could improve academic performance, because experienced teachers are, on average, more effective at raising student test scores. Better retention of teachers could also ease the shortage of fully credentialed teachers in California public schools, because experienced teachers are more likely than new teachers to have full credentials. Thus, retaining teachers could make it less difficult for California to meet the teacher qualification requirements of the federal No Child Left Behind (NCLB) Act. The purpose of this study is to increase understanding of teacher retention in California and of the public policies that could improve it. The following are appended: (1) Data and Methods; (2) Data Means and Model Results; and (3) Teachers in the California Labor Market.