The international project MOSAR was conducted in five rehabilitation centers; patients were screened for rectal carriage of extended-spectrum β-lactamase (ESBL)-producing members of the Enterobacteriaceae. Among 229 Klebsiella pneumoniae isolates, four clonal groups (CG) or complexes (CC) prevailed: CG17 in France, CG101 in Italy, CG15 in Spain, and CC147 in Israel. ESBLs, mainly CTX-Ms, were produced by 226 isolates; three isolates expressed AmpC-like cephalosporinases. High genetic diversity of K. pneumoniae populations was observed, with specific characteristics at each center.