This book constitutes the thoroughly refereed postproceedings of the International Workshop on Trends in Enterprise Application Architecture, TEAA 2005, held in Trondheim, Norway in August 2005 as satellite event of the 31st International Conference on Very Large Data Bases, VLDB 2005. The 10 revised full papers presented together with the abstract of the keynote lecture were carefully reviewed and selected from numerous submissions for inclusion in the book.