Introduction Special Issue on Chains of Commitment Marcus Fontoura i Feature Articles Chains of Commitment Software Architecture Rich Ervin 1 Commitments for Agent-Based Supply Chain Management Mario Verdicchio and Marco Colombetti 13 Reputation and Endorsement for Web Services E. Michael Maximilien and Munindar P. Singh 24 On Handling Component and Transaction Failures in Multi Agent Systems Pradeep Reddy Varakantham, Santosh Kumar Gangwani, and Kamalakar Karlapalem 32 Social ReGreT, a reputation model based on social relations Jordi Sabater and Carles Sierra 44 Conference and Workshop Reports Conference Report: The Third ACM Conference on Electronic Commerce David Parkes 57 ISSN 1551-9031