This four-volume set LNCS 4550-4553 constitutes the refereed proceedings of the 12th International Conference on Human-Computer Interaction, HCII 2007, held in Beijing, china, in July 2007, jointly with 8 other thematically similar conferences.

The 513 revised papers presented in the four volumes were carefully reviewed and selected from numerous submissions. The papers accepted for presentation thoroughly cover the entire field of Human-Computer Interaction, addressing major advances in knowledge and effective use of computers in a variety of application areas.

The 136 papers of this second volume are organized in topical sections on graphical user interfaces and visualization, mobile devices and mobile interaction, virtual environments and 3D interaction, ubiquitous interaction, and emerging interactive technologies.