This book constitutes the refereed proceedings of the 12th IFIP WG 6.12 European Conference on Service-Oriented and Cloud Computing, ESOCC 2026, held in Bolzano, Italy, during September 7–8, 2026.

The 18 full papers and 4 short papers included in this book were carefully reviewed and selected from 40 submissions. They were organized in topical sections as follows: research track and project track.