Bacteria have been around on planet Earth for three billion years or so. In that time they have become adept at protecting themselves against toxic chemicals. Nowhere is this better illustrated than in the case of the development of resistance to antibiotics. Indeed, clinical medicine, as practiced over the last six to seven decades can be viewed as one vast test of the Darwinian thesis “survival of the fittest” as applied to bacteria. That antibiotic resistance is now a major clinical problem all over the world, virtually irrespective of the specific antibiotic, attests to the success and speed of bacterial adaptation. Mechanisms of antibiotic resistance in bacteria are varied and include target protection, target substitution, antibiotic detoxification and block of intracellular antibiotic accumulation. The acquisition of the genes needed to elaborate the various mechanisms is greatly aided by the existence of a variety of promiscuous gene transfer systems, such as bacterial conjugative plasmids, transposable elements and integron systems, that permit movement of genes from one DNA system to another and from one bacterial cell to another, not necessarily one related to the gene donor. Bacterial plasmids serve as scaffolds on which are assembled arrays of antibiotic resistnce genes, acquired in the main by transposition (transposable elements) and site-specific recombination mechanisms (integron gene cassettes), mechanisms that when working in concert are able to construct complex resistance gene arrangements (1). The evidence suggests that ABR-genes in human bacterial pathogens originate from a multitude of bacterial sources, indicating that the genomes of all bacteria can be considered as a single global gene pool into which most, if not all, bacteria can dip for genes necessary for survival. In terms of antibiotic resistance, plasmids serve key roles, particularly as vehicles for resistance gene capture and their dissemination to diverse bacterial species. These various aspects of bacterial resistance to antibiotics will be explored in this presentation.