In this Chapter, we first describe program licensing and the QRIS in California, and we provide an analysis of how well these methods work as tools for monitoring and improving program quality, with special consideration of the Desired Results Developmental Profile (DRDP), the tool most often used to assess children’s developmental levels. We then review various strategies used in California to improve program quality—such as professional development, coaching, and financial aid—and the evidence for their effectiveness. Transitional kindergarten is not included in this chapter because it falls under the K-12 education system requirements, and special education programs are discussed in Chapter 2. In addition to reviewing documents and reports, we conducted interviews with nine people who have a great deal of experience in administrative and policy positions related to early education in California (see Appendix A for a list). (author abstract)