This book constitutes the refereed proceedings of the 18th International Conference on Web and Internet Economics, WINE 2022, which was held Troy, NY, USA in December 2022.The 19 full papers presented together with 19 abstracts in this volume were carefully reviewed and selected from 126 submissions. They were organized in topical sections as follows: theoretical computer science, artificial intelligence, economics, operations research, and applied mathematics.

This book constitutes the refereed proceedings of the 14th International Symposium on Algorithmic Game Theory, SAGT 2021, held in Aarhus, Denmark in September 2021. The 26 full papers presented together with 4 abstract papers were carefully reviewed and selected from 73 submissions. In addition, the volume contains abstracts from 3 invited talks and 2 tutorial talks. The papers are organized in topical sections named: auctions and mechanism design, computational aspects of games, markets and matchings, and social choice and cooperative games.