This SHARE-sponsored issue brief examines child enrollment trends in California's three main public insurance programs: Medi-Cal, Health Families, and Healthy Kids.  The researchers report an overall increase in total enrollment in public insurance programs in California from 2001 through 2007, along with an overall increase in new enrollments (enrollments of children who have not been enrolled in a given program in the prior 12 months), with some variation within programs and over time.  Based on enrollment trends, the authors note that outreach efforts may contribute to the cyclical spikes in new Medi-Cal and Healthy Families enrollments and to the number of children enrolled in the Healthy Kids program.