The Bacterial Evolutionary Epidemiology group uses laboratory experiments, statistical analysis of genomic data and mathematical modelling to improve our understanding of how bacteria diversify and transmit between individuals. Most of our work is focussed on streptococcal pathogens, enteric bacteria and hospital-acquired infections. As well as generating broadly-applicable tools (e.g. PopPUNK, pyseer), we address specific biological questions regarding emerging pathogens, infection control, vaccine design and the spread of antibiotic resistance.