This book constitutes the proceedings of the 16th International Symposium on Algorithmic Game Theory, SAGT 2023, which took place in Egham, UK, in September 2023. 

The 26 full papers included in this book were carefully reviewed and selected from 59 submissions. They were organized in topical sections as follows: ​computational aspects and efficiency in games; computational social choice; fair division; matching and mechanism design.