The presence of antimicrobial resistance (AMR) determinants in the environment enables their dissemination and transfer from and into human microbiomes. Environmental surveillance is a recognized cornerstone for evaluating, understanding, and mitigating emergence and exposure to resistant pathogens. However, despite its growing recognition within European One Health frameworks, environmental surveillance has not yet evolved into a systematic, transmission-oriented approach capable of elucidating pathways of transfer to human pathogens or identifying critical intervention nodes. While human and animal surveillance systems are increasingly harmonized across Europe, environmental AMR data remains fragmented, gathered in a methodologically inconsistent manner, and consequently often treated as unimportant. We argue that environmental surveillance must become a sustained component of Europe’s AMR response, within an effective One Health-based control strategy. Drawing on data collected through a structured comparative policy analysis of 18 national plans against AMR, covering more than 76% of the European population, as well as recent EU-level initiatives (e.g., Eionet pilot study, JAMRAI2, EU-WISH, the European Partnership on One Health Antimicrobial Resistance EUP OHAMR, and the EU Directives 2024/3019, 2026/809), we conclude that despite a common recognition of the importance of the issue and an apparent willingness to evolve, initiatives vary in their focus, resource allocation, methodological approaches, and governance structures. The vast body of gray literature and long-term environmental data that remain underused could contribute to the foundations of harmonization across sectors and international data integration and sharing. Environmental AMR surveillance is an urgent societal, regulatory, and scientific imperative.