This book constitutes the refereed proceedings of the 20th International Conference on Economics of Grids, Clouds, Systems, and Services, GECON 2024, held in Rome, Italy, during September 26–27, 2024.The 12 full papers and 10 short papers presented in this book were carefully reviewed and selected from 37 submissions. They focus on topics such as: Function as a Service: Resource Management and QoS; Cloud Business Models, Pricing, Trading, Network Neutrality; Edge Computing and Energy Awareness; AI/Forecasting/Prediction Sales; and Resource Management in Cloud Applications: Simulation, Streaming Processing and Workflows.