This report analyzes the performance of demand response programs operated by San Diego Gas & Electric and Southern California Edison in summer 2012. It finds that while some programs met or exceeded daily load reduction forecasts, on average the ex post results diverged significantly from forecasts due to inadequate forecasting methods, program design flaws, and non-performance. It also finds that comparing ex post results to resource adequacy forecasts is not a good indicator of performance, and that the utilities used demand response programs fewer times and hours than permitted peaker plant usage. The report provides recommendations to improve demand response program design, operations, forecasting, and coordination with grid operators.