This book constitutes the refereed proceedings of the 29th Annual IFIP WG 11.3 International Working Conference on Data and Applications Security and Privacy, DBSec 2015, held in Fairfax, VA, USA, in July 2015. The 18 revised full papers and 6 short papers presented were carefully reviewed and selected from 45 submissions. The papers are organized in the following topical sections: data anonymization and computation; access control and authorization; user privacy; authentication and information integration; privacy and trust; access control and usage policies; network and internet security; and information flow and inference.