This book constitutes the proceedings of the 20th IFIP WG 8.5 International Conference on Electronic Government, EGOV 2021, held in Granada, Spain, in September 2021, in conjunction with the IFIP WG 8.5 IFIP International Conference on Electronic Participation (ePart 2021) and the International Conference for E-Democracy and Open Government Conference (CeDEM 2021).The 23 full papers presented were carefully reviewed and selected from 63 submissions. The papers are clustered under the following topical sections: digital transformation; digital services and open government; open data: social and technical perspectives; smart cities; and data analytics, decision making, and artificial intelligence.Chapters "Perceived and Actual Lock-in Effects Amongst Swedish Public Sector Organisations when Using a SaaS Solution" and "Ronda: Real-time Data Provision, Processing and Publication for Open Data" are available open access under a Creative Commons Attribution 4.0 International License via link.springer.com.