This book constitutes the refereed procedings of the 5th International Conference on Autonomic and Trusted Computing, ATC 2008, held in Oslo, Norway, in June 2008, co-located with UIC 2008, the 5th International Conference on Ubiquitous Intelligence and Computing.The 25 revised full papers presented together with 26 special session papers and 1 keynote talk were carefully reviewed and selected from 75 submissions. The regular papers are organized in topical sections on intrusion detection, trust, trusted systems and crypto, autonomic computing, organic computing, knowledge and patterns, and pervasive systems. The special session papers cover issues such as organic computing, trust, trust and dependable systems, routing and reliable systems, sensor networks, VoIP, and watermarking.