This volume constitutes the refereed proceedings of the Confederated International Conferences: Cooperative Information Systems, CoopIS 2015, Ontologies, Databases, and Applications of Semantics, ODBASE 2015, and Cloud and Trusted Computing, C&TC, held as part of OTM 2015 in October 2015 in Rhodes, Greece.

The 30 full papers presented together with 15 short papers were carefully reviewed and selected from 144 initial submissions. The OTM program every year covers data and Web semantics, distributed objects, Web services, databases, information systems, enterprise workflow and collaboration, ubiquity, interoperability, mobility, grid and high-performance computing.