China has been introducing antibiotic stewardship policies since the early 2000s to address the persistent and pervasive problem of irrational antibiotic use in hospitals. A recent set of antibiotic stewardship policies were set out between 2011 and 2013 in the Nationwide Special Rectification Campaign on Hospital Antibiotic Use (The Campaign). Drawing on implementation theories, this thesis examines the implementation of The Campaign in respect of factors pertinent to both its context and process, and how these factors interacted. The thesis is based on qualitative data gathered using indepth interviews and semi-structured interviews over two phases of fieldwork. Phase 1 analysed the perspectives of multiple actors at central (governmental organisations) and hospital levels (6 hospitals in urban Beijing, including a national tertiary hospital). Phase 2 – a case study focused on a single hospital – analysed the perspectives of actors from a typical secondary hospital in urban Shanghai. It was found that top-down implementation – characterised by clear line of accountability, target approach, punitive measures and redundancy of policies – was evident at both the central and hospital levels. However, The Campaign’s approach to focus on secondary and tertiary hospitals was strongly shaped by the organisation, delivery and financing of China’s healthcare system and its relevant reforms. Implementation at the hospital level was heavily influenced by contextual factors at system (healthcare system), organisation (hospital and clinical settings) and individual levels (prescribers and patients). Rational prescribing practices were driven in part by The Campaign’s interaction with some of those factors, but more crucially by frontline implementers’ active adaptation in response to the local context and needs. In recognising the potential of the top-down approach, the findings also highlight the need to better involve frontline implementers, align wholistic healthcare reforms and understand the complexity of policy interactions in the implementation of antibiotic stewardship.