This study comprehensively and meticulously addresses the taxation of special regimes for taxpayers with lower contributory capacity in Latin American countries. It encompasses both the theoretical aspects of their design (objectives, characteristics, subjects, scope, tax calculation - presumptive technique -, general features such as uniqueness or multiplicity, substituted taxes and social security resources, and trends in their application) and a practical analysis of these regimes (collecting experiences from their application in recent decades, conducting a critical analysis of best practices, and identifying unintended side effects).