Many observers have argued that California’s system of local government is too complex and fragmented. They contend that such complexity hinders coordination among governmental activities, makes it difficult to establish political accountability, and may lead to inefficient provision of services. Some have further argued that the passage of Proposition 13 in 1978 exacerbated the problem, leading to a proliferation of new cities and special districts and fundamentally altering California’s local governance structure. This report examines the long-term trends in California’s local government structure and the possible effects of Proposition 13. It presents a new, more accurate method for measuring local government fragmentation and illuminates the factors that contribute to differences in local political structure around the state.