This study analyzes a range of energyefficiency options available in Mexico, includingsupply-side efficiency improvements in the electric powerand oil and gas industries and demand-side electricityefficiency measures to limit high-growth energy-consumingactivities, such as air conditioning and refrigeration. Italso evaluates a range of renewable energy options that makeuse of the country's vast wind, solar, biomass, hydro,and geothermal resources. But low-carbon (CO2) developmentis not only about energy production and consumption. InMexico one of the most important sources of greenhouse gasemissions continues to be emissions from deforestation. Therate of deforestation has fallen steadily in Mexico over thepast decades. Expanded programs for forest management,wildlife conservation, and efforts to increase the stock offorests can provide needed employment in rural areas andhelp make Mexican forests net absorbers of CO2 in the comingyears. A fundamental question often asked about low-costmitigation options is why they are not already beingundertaken. As the study shows, the availability ofcommercial technology and even low financial costs is oftennot enough to overcome barriers related to institutional andknowledge gaps, regulatory and legal constraints, orsocietal norms. Inability to surmount these'transactions costs' is typically at the root ofthe problem of why supposedly low-cost actions are notundertaken. To partially overcome this dilemma, one of theexplicit criteria used in this study for identifyinglow-carbon measures was that they had already beenimplemented on some scale in Mexico or in a similar economyoutside of Mexico. In order to mainstream low-carbondevelopment, a package of new stimuli will be needed,including public and consumer education and training, publicdemonstrations, standards and regulations, and financial incentives.