This volume constitutes the refereed proceedings of the Third International Conference on Internationalization, Design and Global Development, IDGD 2009, held in San Diego, CA, USA, in July 2009 in the framework of the 13th International Conference on Human-Computer Interaction, HCII 2009 with 10 other thematically similar conferences. The 57 revised papers presented were carefully reviewed and selected from numerous submissions. The papers accepted for presentation thoroughly cover the entire field of internationalization, design and global development and address the following major topics: cross-cultural user interface design; culture, community, collaboration and learning; internationalization and usability; ICT for global development; and designing for eCommerce, eBusiness and eBanking.