This book presents the proceedings of the Third International Conference on Trust, Privacy and Security in Digital Business (TrustBus 2006), held in Kraków, Poland, September 5-7, 2006. The conference continues from previous events held in Zaragoza (2004) and Copenhagen (2005), and maintains the aim of bringing together academic researchers and industry developers to discuss the state of the art in technology for establishing trust, privacy and security in digital business. We thank the attendees for coming to Kraków to participate and debate the new emerging advances in this area. The conference programme included two keynote presentations, one panel session and eight technical papers sessions. The keynote speeches were delivered by Jeremy Ward from Symantec EMEA on the topic of “Building the Information Assurance Community of Purpose”, and by Günter Karjoth from IBM Research - Zurich, with a talk entitled “Privacy Practices and Economics –– From Privacy Policies to Privacy SLAs. ” The subject of the panel discussion was “Is Security Without Trust Feasible?” chaired by Leszek T. Lilien from Western Michigan University, USA. The reviewed paper sessions covered a broad range of topics, from access control models to security and risk management, and from privacy and identity management to security protocols. The conference attracted 70 submissions, each of which was assigned to four referees for review. The Programme Committee ultimately accepted 24 papers for inclusion, which were revised based upon comments from their reviews.