BackgroundAs the antimicrobial resistance (AMR) problem accelerates, humans and animals are suffering from the consequences of infections with diminishing antimicrobial treatment options. Within the One Medicine and One Health mandate, which denotes a collaborative, multisectoral, and transdisciplinary approach to improve medicine and health across human and animal sectors, we investigate how human and veterinary medical practitioners apply their medical and policy knowledge in prescribing antimicrobials. Different regions and locations establish different intermediary policies and programs to support clinicians in that pursuit. In Hong Kong, there are locally adapted programs at governance and clinical levels in the human medical field. However, there is no locally adapted veterinary antibiotic prescription guideline or stewardship program, and veterinarians adopt overseas or international professions' antimicrobial use guidelines. Such a policy environment creates a natural experiment to compare local policy implementation conditions and clinicians' knowledge, perception, and practice. MethodWe construct the investigative survey tool by adaptation of Knowledge, Attitude, and Practice (KAP) and Capacity, Opportunity, and Motivation-Behavior (COMB) models. We identify, compare and contrast factors that influence clinicians' antimicrobial prescription behavior. The factors are considered both intrinsically, such as personal attributes, and extrinsically, such as societal and professional norms. FindingsThe absence of locally adopted antimicrobial guidelines influences AMR stewardship program implementation in local Hong Kong veterinary community. As medical allies, physicians and veterinarians share similar demographic influence, organization considerations and perception of public awareness. Both cohorts prescribe more prudently with more years-in-practice, time available to communicate with patients or caretakers, and public awareness and support.