Introduction: This article presents an experimental multisource surveillance system for acute poisonings that occurred in the Île-de-France region in 2010 and 2011, encompassing all circumstances and severity categories. Methods: The study is based on a descriptive analysis of symptomatic poisoning cases extracted from: a) the databases of the Toxicological Emergency Hotline (RTU) operated by the Paris Poison Control Center (CAP); b) an emergency department (ED) participating in the OSCOUR® network; c) a medical and toxicological intensive care unit (RMT), d) the Île-de-France Regional Pharmacovigilance Coordination (CRPV); and e) two toxicology laboratories conducting forensic examinations following out-of-hospital deaths. Out-of-hospital deaths were prospectively collected in 2014. Results: The CAP recorded, on an annual average, 9,520 cases of poisoning (male-to-female ratio = 0.77), corresponding mainly to accidental poisonings of young children. The other partners identified 2,980 cases for the ED, 270 for the RMT, 45 for the CRPV, and 207 for toxic deaths. The profile of poisoned individuals differs significantly from one source to another, as partners other than the CAP primarily handle intentional poisonings involving adults, among which drug poisonings—whether or not associated with alcohol—predominate. Conclusion: Although there is room for improvement, this first multi-partner collaboration confirms the value and feasibility of enhancing our understanding of the epidemiology of acute poisonings through the diverse perspectives of each partner.