This book constitutes the revised selected papers of the 6th Ibero-American Congress on Smart Cities, ICSC-Cities 2023, held in Mexico City and Cuernavaca, Mexico, during November 13–17, 2023. The 19 full papers included in this book were carefully reviewed and selected from 94 submissions. They were organized in topical sections as follows: Urban Informatics for Smart Cities; Optimization, Smart Industry, and Smart Public Services; Internet of Things; Computational Intelligence and Urban Informatics for Smart Cities and Innovative Informatic Approaches for Smart Cities.