In recent years, compelling research has found that mastery of early math concepts at a preschool level is a better predictor of later academic outcomes than literacy. Partly driven by these findings, increasing attention is being focused on improving math pedagogy at the preschool level. The issue has assumed added urgency as a result of California's adoption of the Common Core State Standards, as well as the roll out of transitional kindergarten, the first new "grade" in state schools in more than a century. Several convenings, underwritten by the Heising-Simons Foundation, have been held during the past year in California focusing on early math at a national, state and local level. This working paper emerged from two convenings held at California State University, East Bay and the University of California Irvine, sponsored by the California STEM Learning Network (CSLNet), which focused on the policy and practical challenges for introducing a more comprehensive math curriculum at a local level, especially in preschools. This paper supplements two previous papers written by Deborah Stipek and Alan Schoenfeld based on convenings held at Stanford University and the University of California Berkeley in November 2011 and January 2012, respectively. This paper identifies several key challenges based on discussions at the Cal State East Bay and UC Irvine meetings, as well as follow-up interviews with program administrators, educators involved with teacher training and other experts in preschool education in California. These challenges include: (1) the paucity of math content in preschool teacher preparation and permit requirements; (2) the lack of preschool professional development and in-service training; (3) the barriers imposed by "math anxiety" among preschool teaching staff; (4) linking the preschool experience with what awaits children in K-3 grades; and (5) the impact of the state's budget crisis on the capacity of state agencies, education institutions and preschool programs to respond to these challenges. On a broader level, California also faces the challenge of how to reach the hundreds of thousands of children who are not enrolled in state-supported preschool programs, and who may not have adequate exposure to math concepts before they reach transitional kindergarten or kindergarten proper. (Contains 2 tables, 1 figure, 1 online resource, and 26 endnotes.) [This report was written with support from the California STEM Learning Network (CSLNet).]