The occupational safety and health (OSH) of posted workers is regulated by Article 3 of the Directive 96/71/EC concerning the posting of workers in the framework of provision of services and is inextricably linked to the assurance of decent labour/working conditions. In most cases, serious infringements in matters of OSH go hand in hand with underpayment, excessive working time, lack of rest periods, lack of preventive measures, non-compliance with regulations concerning social security and health insurance and underestimating the challenges concerning OSH in culturally and ethnically diverse workspaces. This inevitably leads to higher prevalence of work-related accidents, especially in high-risk, hazardous sectors and can have short-term and long-term effects (i.e. burnout, disabilities, and chronic conditions) on the health of posted workers. The disputes about the responsibility of assuring OSH in the context of subcontracting chains and liability in cases of accident further exacerbate vulnerabilities of posted workers. The project activities focus on the under-researched, underexposed and poorly addressed issue of labour/ working conditions and OSH of posted workers. While current research and policy-oriented initiatives tend to focus on issues such as tax avoidance, fictitious postings, social benefit frauds and challenges in establishing cooperation and information sharing on breaches of the relevant Directives between national competent authorities via the IMI system, more attention should also be placed on the assurance of decent working conditions, occupational safety and health, assessment of health-related risks, prevention measures and monitoring.