Dr Coffey's career started with investigations into the mechanisms of resistance to antibiotics, including penicillin and cephalosporins, of the successful human pathogen Streptococcus pneumoniae, one of the common causative agents of bacterial pneumonia, meningitis and otitis media. Work included analysing the role of interspecies recombination and then investigations into the ability of the pathogen to utilize capsular switching as a means of immune evasion. Dr Coffey was also involved with the adaptation of a new tool, multilocus sequence typing or MLST, for identifying strains of bacterial pathogens and the analysis of molecular epidemiology. This work was originally conducted at the University of Sussex before relocation to the University of Oxford in 1997. A burgeoning interest in veterinary streptococcal species and a new challenge ended up in a move to the Institute for Animal Health, Compton, in 2000. During Dr Coffey's time at the IAH, the main interest of the group was the application of molecular techniques for the investigation of host:pathogen interaction in the pathogenesis of bacterial disease. This included a collaborative MLST study of Streptococcus uberis and numerous studies into the pathogenesis of bovine tuberculosis. Work expanded to include investigations into key immune genes and studies at the genome level. Studies of immune genes are looking at variability at the gene level and potential correlations with disease. More recently the research interests have included studies into the pathogenesis of bovine mastitis caused by Streptococcus uberis. The main aim of these projects has been a better understanding of the bovine immune response to economically important pathogens, and to identify potential correlates of disease and potential avenues for immune intervention. This work is now continuing at the School of Veterinary Medicine & Science at the University of Nottingham following a move in the summer of 2011.