Scientists introduced the dilution‑and‑delay (DnD) susceptibility assay, a high‑resolution, high‑throughput method designed to detect low‑frequency or masked antibiotic resistance that escapes standard diagnostics. Published in Nature Communications, the technique promises faster, more granular mapping of bacterial responses to antibiotics in clinical and research settings. The DnD assay combines time‑resolved growth measurements with graded antibiotic exposures to reveal delayed growth recovery and subpopulations that survive initial treatment—signals indicative of heteroresistance or inducible mechanisms. Authors argue the method could change antimicrobial stewardship by identifying resistance pathways earlier and informing combination therapies. Because conventional susceptibility tests can miss subpopulations that drive treatment failure, a scalable assay that resolves temporal dynamics could improve clinical decision making and surveillance for emerging resistance.