The European Union’s environmental and sustainability legislation is structured through a series of directives and regulations, each targeting specific areas such as waste management, water quality, air pollution, biodiversity conservation, chemical safety, renewable energy, energy efficiency, and climate change mitigation. Below is a detailed examination of these legislative instruments, highlighting their objectives, scope, and mechanisms. Moreover, the Court of Justice of the European Union (abbr. CJEU) has played a pivotal role in interpreting and enforcing EU environmental and sustainability legislation. Through its judgments, the Court ensures that Member States comply with their obligations under various directives and regulations on (i) environmental protection, (ii) energy, (iii) climate protection, (iv) circular economy, and (v) reporting.