In this session, we will walk through the fundamentals of AST — from why we test, to the reference methods that underpin every microbiology platform in our laboratories, to how breakpoints are set and what the abbreviations S, I, and R really mean for the patient at the other end of that result. Whether you are new to the bench or looking to refresh your foundations, this session speaks directly to the laboratory’s role as the bridge between the organism identified and the prescription.