For 150 years California met water needs primarily through expensive surface water reservoirs and increased groundwater pumping. This approach to water management was emulated around the world. Today, however, budget deficits, climate change and competing interest all strain California's ability to meet new needs for a growing population, the economy and the environment. Water for California and the Planning & Conservation League led an effort to assess viable options for California under these new realities. The resulting Investment Strategy for California Water identifies cost-effective, environmentally beneficial and socially acceptable water management strategies for meeting these needs. The Strategy demonstrates how California can more than meet water supply needs with locally planned and implemented programs such as water conservation, recycling and groundwater treatment. As with past California approaches to water management, this Strategy can be useful to other regions facing similar challenges.