The complex framework of Brazil’s environmental federalism emerges from the interplay of powers among its federative entities—federal, state, and municipal—guided by the 1988 Constitution. This framework distributes both administrative and legislative competences to ensure ecological protection while fostering a balance between unity and autonomy. Administrative authority, shared by all entities, empowers them to regulate, monitor, and protect natural and cultural resources. Yet, the Constitution also delineates exclusive powers, such as federal oversight of nuclear energy and state authority over gas services, illustrating the nuanced distribution of responsibilities. Legislatively, Brazil employs a concurrent model, allowing all entities to enact laws on shared concerns like environmental preservation. Federal laws set general provisions, while states and municipalities legislate specifics, considering regional and local peculiarities. This dynamic often provokes disputes, as seen in conflicts over asbestos regulation and GMO cultivation, which require judicial intervention to harmonize competing interests. Supplementary Law n. 140/2011 seeks to mitigate such conflicts, fostering cooperation among entities. Nevertheless, the enduring challenge lies in balancing regional autonomy with national coherence, a delicate equilibrium where local interest collides with overarching ecological imperatives. Thus unfolds a federalism that aspires to reconcile Brazil’s diverse landscapes with the shared imperative of environmental stewardship.