Although the potential for horizontally transmitted antibiotic resistance in the microbiome appears to be enormous, the available evidence indicates that mechanisms of selection and transmission progressively refine and fine-tune the gene pool. This biodiversity contraction can be readily exploited for the bedside diagnosis of antibiotic susceptibility but raises the spectre of a global biodiversity threat. Current approaches to managing antibiotics and antibiotic resistance include in-time recognition of resistance potential and transmissibility, and defining antimicrobial impact on the microbiome. This may include options for restitution of normal balance in the microbiota overall and even reversing the global progress of highly transmissible antimicrobial resistance through a probiotic approach to the major vehicles of the horizontal gene pool itself .