Description:The two volume set LNCS 4662 and LNCS 4663 constitutes the refereed proceedings of the 11th IFIP TC13 International Conference on Human-Computer Interaction, INTERACT 2007, held in Rio de Janeiro, Brazil, in September 2007. The 60 revised papers of the first volume presented together with the abstracts of 3 keynote talks were carefully reviewed and selected from numerous submissions. The papers are organized in topical sections on social computing, Web, UI prototyping, user centred design methods and techniques intelligent user interfaces, interaction on the move, accessibility, designing for multiples devices, interaction techniques, affective computing, 3D interaction and 3D interfaces, as well evaluation methods.