Direct ethanol fuel cells (DEFCs) belong to the family of proton exchange membrane fuel cells (PEMFCs), in which ethanol is directly used as the fuel. In the present work, the main aspects related to DEFCs such as electrocatalysts, membrane electrode assembly (MEA) preparation and their corresponding effects on the total cell performance are summarized and discussed. Furthermore, the issues about the disadvantages such as ethanol crossover and the electrolyte membrane's thermal and mechanical stability, as well as the challenges for DEFC's rapid development and commercialization are addressed. (c) 2005 Elsevier B.V. All rights reserved.