The report analyzes health insurance trends for non-elderly adults in the United States and California from 2000 to 2004, and estimates the impact of premium price increases on health insurance coverage over this period. The study finds that over the last five years, there were important shifts for all non-elderly persons from employer-based coverage to unemployment and increased enrollment in public programs. However, the outcomes have been different for adults than for children, mainly because children have been the main beneficiaries of new public health programs and increased public coverage. Meanwhile, the majority of adults who have lost employer-based health coverage have become uninsured. Considering adults in California, and taking into account projected population growth, the study simulates future coverage rates for California between the years 2005 to 2010.