A collection of Viridans isolates covering 24 taxonomically designated species, including Type strains, all those analysed previously using MLSA, those strains utilized for sera production for pneumococcal serotyping and covering a broad geographic and temporal span will be sequenced and utilized to form a firstly to place new genomes into ‘species clusters’ and then to further delineate based on genomic similarity. While the focus is on the utility for the pneumococcal community more broadly, this collection will allow us to address a number of questions. A detailed understanding of the pan genome of Viridans streptococci with the purpose of developing easy to use, intuitive tools for the placing of new strains into sequence clusters. -An investigation into the horizontal exchange of DNA, in particular the capsular biosynthetic locus (cps ) , the products of which determine the pneumococcal capsular polysaccharide type (CPS) - the basis of current vaccine targets. This project will allow the establishment of a solid baseline population structure of major and minor sequence clusters (as a proxy for speciation) within the Viridans streptococci and, in combination with existing sequence datasets from the pneumococcus, will form a solid basis for initial ‘speciation’ and fine scale clustering within lineages. Data will be provided through cGPS within a web application (www.wgsa.net) allowing the interrogation of metadata in a genomic context and forming a solid resource for the public health community