This book constitutes the refereed conference proceedings of the 12th IFIP WG 6.11 Conference on e-Business, e-Services and e-Society, I3E 2013, held in Athens, Greece, in April 2013. The 25 revised papers presented together with a keynote speech were carefully reviewed and selected from numerous submissions. They are organized in the following topical sections: trust and privacy; security, access control and legal requirements in cloud systems; protocols, regulation and social networking; adoption issues in e/m-services; new services adoption and ecological behavior; knowledge management and business processes; and management, policies and technologies in e/m-services.