The 8th International Workshop on Fuzzy Logic and Applications (WILF 2009) held in Palermo (Italy), June 9-12, 2009, covered topics related to theoretical and experimental areas of fuzzy sets and systems with emphasis on di?erent applications. This eventrepresentsthe continuation ofan established traditionof biannual interdisciplinary meetings. The previous editions of WILF were held, with an increasing number of participants, in Naples (1995), Bari (1997), Genoa (1999), Milan (2001), Naples (2003), Crema (2005) and Camogli (2007). Each event focused on distinct main thematic areas of fuzzy logic and related applications. WILF 2009 aimed to highlight connections and synergiesof fuzzy sets theory with nonconventional computing (e.g., neural networks, evolutionary compu- tion, support vector machines, molecular computing, quantum computing) and cognitivescience, inordertoreachabetterunderstandingofbothnaturaland- ti?cial complex systems as well as computing systems, inspired by nature, which are able to solve complex problems. From this perspective one of the main goals of the WILF workshops is to bring together researchers and developers from both academia and high-tech companies. WILF 2009receivedmorethan 60 paper submissionsfrom all overthe world, including Algeria, Belgium, Benin, Brazil, Canada, China, France, Greece, India, Iran, Italy, Japan, Poland, Romania, Slovakia, Spain and the USA. A rigorous peer-review selection process was applied to ultimately select nearly 40 high-quality manuscripts to be published in this volume. Moreover, thevolumealsoincludespresentationsfromthreekeynotespeakers EtienneKerre(GhentUniversity, Belgium), SankarK.Pal(ISI, India)andEnric Trillas (ECSC, Spain).