A major energy challenge of the 21(st) century is the health and welfare of 2.7 billion people worldwide, who currently rely on burning biomass in traditional household cooking systems. This Special Issue on Clean Cooking Fuels and Technologies in Developing Economies builds upon an IAEE workshop on this subject, held in Istanbul in 2008 (Foell et al., 2008). It includes several papers from that workshop plus papers commissioned afterwards. The major themes of that workshop and this Special Issue are: Analytical and decision frameworks for analysis and policy development for clean cooking fuels. Making energy provisioning a central component of development strategies. Strategies/business models of suppliers of modern fuels and technologies. Analysis of successes/failures of past policies and programs to improve access to clean cooking. This introductory paper serves as a preamble to the 11 papers in this Special Issue. It provides a brief background on household cooking fuels and technologies, including: (1) their implications for sustainable development, health and welfare, gender impacts, and environment/climate issues; (2) options and scenarios for improved household cooling systems; and (3) discussions of institutions, programs and markets. It closes with "Research and Action Agendas", initially developed during the 2008 workshop. (C) 2011 Elsevier Ltd. All rights reserved.