The book "Enterprise Information Systems VI" presents a collection of the best contributions from the sixth International Conference on Enterprise Information Systems (ICEIS 2004), which took place in Porto, Portugal. Organized by INSTICC in collaboration with the Portucalense University, ICEIS has evolved since its inception in 1999 into a significant forum for the exchange between researchers, engineers, and practitioners in the field of business applications of information systems. The conference attracts a growing interest from the international academic community each year and is now considered one of the largest of its kind worldwide. This year, five parallel tracks were offered, covering various aspects of enterprise computing, including databases, artificial intelligence, information systems analysis, software agents, and human-computer interaction. The sections of the book reflect the themes of the conference and provide valuable insights into current developments and challenges in this dynamic field.