Between December 24, 2012, and January 8, 2013, 10 cases of salmonellosis were reported by the Paris Maternal and Child Health Service (PMI) among children attending four daycare centers in the 7th arrondissement. Subsequently, the National Reference Center for Salmonella noted an increase in salmonellosis cases in Paris in December 2012 and identified, in some cases, a single strain that had rarely been encountered until then. Investigations identified 34 cases of salmonellosis (30 confirmed cases and 4 probable cases), including 10 children attending daycare centers and 24 community cases. The outbreak lasted 10 weeks and involved two strains of Salmonella: one of serotype Typhimurium and Crispol type 51 (CT51), and the other of serotype 4,12:i:-, a monophasic variant of serotype Typhimurium and CT1. The cases were specifically questioned about their dietary habits. Most of them had visited a caterer in Paris’s 7th arrondissement in the days leading up to the onset of symptoms. An unannounced inspection by the Paris Departmental Directorate for Public Health revealed numerous violations at this establishment. Samples taken on-site led to the isolation of the S. Typhimurium CT51 and S. 4,12:i:- CT1 strains on surfaces and in products sold by the caterer. This investigation underscores the importance of maintaining strict hygiene standards and temperature control at catering establishments. It also highlights the role played by the PMI’s observation and early reporting. This report constituted the “visible” part of a larger-scale outbreak, which involved both institutional and community cases, occurring simultaneously.