This paper presents the results of a study of household conservation response to the California energy supply crises during the summer of 2001 and in the post-crisis year of 2002. It draws upon two statewide telephone survey waves, with matched consumption information from customer electricity bills, and weather data from various parts of the state. The analysis explores conservation behavior, energy attitudes, social and housing demographics, and estimated energy savings. We found that the conservation response to the crisis exceeded expectations in the energy policy community, with consumers showing surprising flexibility in their energy demands, and for reasons other than energy prices. While conservation actions (both behavioral and hardware purchase) were reported by a large majority of households, they were also somewhat socially segmented, and the resulting energy savings were not evenly distributed across the population. There was persistence of conservation a year after the crisis, as well as continuing concern by consumers about energy-related issues. As a result of the crisis experience, the routine functioning of the energy system seems to have been ""problematized"" for many Californians. Some implications of these findings for future energy efficiency and renewable energy policies are considered.