Six and one-half million Californians were uninsured for all or some of 2005, a number that is as large as the combined populations of nine other states. The number of uninsured represented one in five children and nonelderly adults, a rate that was slightly lower than in 2003 due to California's tight labor markets and expanding enrollment and retention in California's public coverage programs for children. These marginal improvements are unlikely to continue unabated given the instability of employment-based insurance coverage in the face of rising costs. In this policy brief, we compare insurance coverage over time using the California Health Interview Surveys conducted in 2001, 2003 and 2005. We look at the type of coverage over the past 12 months for both children and nonelederly adults.