Antimicrobial resistance (AMR) has become, in the last two decades, a global threat that poses potentially dramatic health and economic consequences. AMR is referring to antibacterial, antiviral and antifungal resistance. Although it remains a complex issue, antibacterial resistance is, presently, of greatest concern and the main drivers of AMR are antimicrobial overuse and misuse in human, animal, agricultural and environmental sectors and the spread of resistant bacteria and resistance determinants within and between these sectors and across countries. This document aims to provide an overview of how OECD member countries assess AMR of microorganisms used as biopesticides and summarise the available approaches. The aspiration is that the document also highlights the main issues to be considered during the evaluation of the AMR potential of microorganisms used as plant protection products.