<jats:title>Abstract</jats:title><jats:p>Recent reports indicate the emergence of a new carbapenemase producing <jats:italic>Klebsiella pneumoniae</jats:italic> clone, ST307. Here we show that ST307 emerged in the mid-1990s (nearly 20 years prior to its first report), is already globally distributed and is intimately associated with a conserved plasmid harbouring the <jats:italic>bla</jats:italic><jats:sub>CTX-M-15</jats:sub> extended-spectrum beta-lactamase (ESBL) gene plus other antimicrobial resistance determinants. Our findings support the need for enhanced surveillance of this widespread ESBL clone in which carbapenem resistance is now emerging.</jats:p>