This brief identifies important elements of high-quality early childhood education programs as indicated by research and professional standards. These include: (1) Early learning standards and curricula that address the whole child, are developmentally appropriate, and are effectively implemented; (2) Assessments that consider children's academic, social-emotional, and physical progress and contribute to instructional and program planning; (3) Well-prepared teachers who provide engaging interactions and classroom environments that support learning; (4) Ongoing support for teachers, including coaching and mentoring; (5) Support for English learners and students with special needs; (6) Meaningful family engagement; (7) Sufficient learning time; (8) Small class sizes with low student-teacher ratios; (9) Program assessments that measure structural quality and classroom interactions; and (10) A well-implemented state quality rating and improvement system. These high-quality building blocks should be at the forefront in revising California's early childhood education system.