This update of the Overview of Tax Administrations in CIAT Countries has been conducted based on the data provided by the ISORA survey, collected during 2022 with information from 174 countries referring to the year 2021. The information has been synthesized into four major categories: 1) administered taxes, collection, and budget; 2) available human resources; 3) organization and operational functioning; and 4) innovative techniques and information and communication technologies (ICT).