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IbPRIA 2011 (Iberian Conference on Pattern Recognition and Image Analysis) is the fifth edition of a series of similar events organized every 2 years by Asociación Española de Reconocimiento de Formas y Análisis de Imágenes (AERFAI) and Associação Portuguesa de Reconhecimento de Padrões (APRP). In previous editions it was celebrated respectively in Andraxt, Spain (2003), Estoril, Portugal (2005), Girona, Spain (2007) and Póvoa de Varzim, Portugal (2009). IbPIA 2011 was held in Las Palmas de Gran Canaria, Spain from June 8 to 10, 2011.

IbPRIA 2011 attracted 158 papers. After the reviewing process 34 papers were accepted for oral presentation. This special issue of the Pattern Recognition journal includes contributions which are substantially extended and revised versions of papers selected from the best presented at IbPRIA 2011. The papers cover topics in theoretical Pattern Recognition, Statistical Machine Translation, Shape and Object Recognition, Biomedical Image Analysis and Face Recognition.