This book constitutes the refereed proceedings of the Third International Conference on Formal Concept Analysis, ICFCA 2005, held in Lens, France in February 2005.

The 28 revised full papers presented together with an invited paper were carefully reviewed and selected for inclusion in the book. The papers reflect both progress in the foundational theory of formal concept analysis and its practical applications; algorithmic aspects are discussed as well as efforts to broaden the field.