This book constitutes the refereed proceedings of the 19th International Conference on Metaverse, METAVERSE 2023, held in Honolulu, HI, USA, during September 23–26, 2023.

The 9 full papers and 3 short papers included in this book were carefully reviewed and selected from 15 submissions. They were organized in topical sections as follows: answer set programming; metaverse engineering foundations and applications, with a focus on novel approaches for engineering requirements, design and architectures, testing, maintenance and evolution, model-driven development, software processes, metrics, quality assurance and new software economics models, search-based software engineering, benefiting day-to-day services sectors and derived through experiences, with appreciation to scale, pragmatism, transparency, compliance and/or dependability.

This book constitutes the refereed proceedings of the 20th International Conference on Metaverse – METAVERSE 2024, held in Bangkok, Thailand, during November 16–19, 2024.

The 6 full papers and 4 short papers included in this book were carefully reviewed and selected from 22 submissions. They were organized in topical sections as follows: research track; application and industry track; and short paper track.

This book constitutes the refereed proceedings of the 19th International Conference on Metaverse, METAVERSE 2023, held in Honolulu, HI, USA, during September 23–26, 2023.

The 9 full papers and 3 short papers included in this book were carefully reviewed and selected from 15 submissions. They were organized in topical sections as follows: answer set programming; metaverse engineering foundations and applications, with a focus on novel approaches for engineering requirements, design and architectures, testing, maintenance and evolution, model-driven development, software processes, metrics, quality assurance and new software economics models, search-based software engineering, benefiting day-to-day services sectors and derived through experiences, with appreciation to scale, pragmatism, transparency, compliance and/or dependability.

This book constitutes the refereed proceedings of the 20th International Conference on Metaverse – METAVERSE 2024, held in Bangkok, Thailand, during November 16–19, 2024.

The 6 full papers and 4 short papers included in this book were carefully reviewed and selected from 22 submissions. They were organized in topical sections as follows: research track; application and industry track; and short paper track.