Brazil was the first low‐ and middle‐income country to provide universal treatment access to people living with the acquired immunodeficiency syndrome (AIDS), becoming a widely acclaimed model for best practice to managing this epidemic. However, we know little about important challenges to the key pillars of Brazil's response. This article discusses how the evolution of the country's health system institutions and international advancements in AIDS treatment and prevention affected the national response. Decentralization of health system resources and policy making brought fresh challenges to the centralized governance of the national AIDS program and to civil society, weakening their coordination and advocacy capacity. Regardless, AIDS treatment and prevention strategies in Brazil remain aligned with the current international protocols, but unfortunately have been restricted in some geographic areas and/or populations.