Antimicrobial resistance (AMR) is a growing global problem. Like many other public health issues, research points to the important role of structural factors in shaping the emergence, transmission and burden of AMR. However, mirroring other areas of public health, the evidence-base of interventions that address these structural issues is slim and infrequently synthesised. Structural interventions (SIs) seek to alter the context that produces or co-produces ill-health4. AMR has been configured as a One Health problem to be understood in terms of human-animal-environment interconnections. Infection control and prevention is recognised as essential to addressing AMR, but how best to achieve this through a One Health perspective remains a challenge. This review addresses this gap by identifying and synthesising evidence of interventions that operate on a structural level to Improve water, hygiene, sanitation and biosecurity in communities that live and/or work with animals In Low- and Middle-Income Countries (LMICs). The premise of this review is that interventions to improve water, sanitation, hygiene (WASH), and biosecurity intend to reduce burdens of infection and have the potential to reduce reliance on antibiotics for humans and animals. Therefore, such interventions have the ability to reduce both transmission and emergence of AMR. Two further observations inform the focus of this review: growing evidence of the insufficiency of purely technical or behavioural WASH/biosecurity Interventions to reduce disease burdens across LMICs, accompanied by calls for structural Interventions; and that most reviews retain classificatory silos of either human WASH or animal biosecurity which belies the realities of many rural and urban populations whose lives are interconnected with animals across LMIC settings. This review, therefore, addresses the potential for structural interventions on WASH/biosecurity to have an impact on Infections, antibiotic use and AMR in LMICs. Methodologically, this review is influenced by impact assessments in development studies, where interventions are often complex in design and implementation and their effects multifaceted. The kinds of intervention that operate at a structural level are similarly challenging to identify and to characterise neatly, and are unlikely to be restricted to a randomised controlled trial design. Therefore, our search criteria and strategy are wide and our methods mixed, in order to capture potential interventions that could have an impact on our set of outcomes. In addition, in this review we recognise that interventions have impacts beyond a particular pre-defined outcome, and to be able to recommend a particular intervention strategy requires consideration of not only what that intervention comprised and required, but also what unintended consequences or co-benefits the intervention may have produced. Finally, a key consideration for this review is that many studies undertaken in Spanish, Portuguese and French speaking countries, where different interventions may have been developed and piloted, can be excluded due to language criteria, and in this case, we deliberately include studies in these languages in addition to English in the search and review. This systematic review will summarise evidence on how WASH and biosecurity interventions could have the potential to reduce the burden of infections, antimicrobial use and/or AMR in animal agriculture and in people in contact with animals in different country settings, with a focus on LMICs. WASH and biosecurity interventions for reducing burdens of infection, antibiotic use and antimicrobial resistance: a One Health mixed methods systematic review Included studies have to examine the impact of WASH and biosecurity interventions on reducing burden of infections and therefore promote healthier production systems where the use of antibiotics is reduced or limited. Our review will categorise these interventions according to the context where they were performed (e.g., LMICs country, region, urban or rural, type of productions systems, livelihoods systems, agroecological situation, beneficiaries, climate conditions). The aim of this study is to identify points for WASH and biosecurity interventions at structural and system levels that will enable reduction in reliance on antibiotics in the everyday lives of people living with animals in urbanised and rural landscapes.