Lighting, primarily with incandescent bulbs, is the major end use of electricity in Mexican homes. The introduction of compact fluorescent lamps (CFLs) could significantly reduce electricity use in lighting. We describe a survey of lighting use in homes of Guadalajara and Monterrey, Mexico, that was conducted to provide information to determine the potential for CFLs. The results show that 1/6 of the incandescent bulbs can be replaced with CFLs if only those bulbs used more than 4 hours per day are targeted. We also provide insights on conducting similar surveys in other developing countries.