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Volcanogenic massive sulfide (VMS) deposits are the most conspicuous type of deposits that formed during the Mesozoic inMexico.ManyMexicanVMS deposits display "classical" Kuroko-typemineral zonation and structure, and some of them, as Cuale and La Minita formed in shallowsubmarine environments. Themost prospective time window for the formation of VMS deposits in Mexico comprises the Late Jurassic and the Early Cretaceous. VMS stopped forming during the progressive continentalization of Mexico, since its metallotectonic processes (dominated by extensive tectonics) changed givingway to compression during the late Early Cretaceous; newVMS deposits did not form until after the opening of the Gulf of California.MesozoicVMS deposits inMexico occur in submarine volcano-sedimentary sequences that deposited essentially in association with back-arc basins (now found roughly along the boundaries between tectonostratigraphic terranes) or within juvenile and slightly evolved arcs (at the internal parts of the terranes), while few others occur on the epicontinental seafloor and hinterlands of eastern Mexico. VMS deposits are especially abundant in the Guerrero composite terrane, and are also present in the Alisitos and Parral terranes.However, new evidence referred in this paper indicate the western continental edge of the cratonic block of Oaxaquia as a promising, new prospective region for VMS deposits.Interestingly, no VMS deposits are found in the northern part of the Guerrero composite terrane despite the occurrence of marine volcano-sedimentary sequences similar to those in the south; such absence can be related to differential extensional unroofing, much larger in the southern part of the Guerrero composite terrane than in the northern part.Many VMS deposits occur along or close to terrane boundaries, especially around the Guerrero composite terrane. This distribution reflects the association between VMS deposits and back-arc basins, which represented the frontal part of terranes or sub-terranes that were ultimately accreted to the Oaxaquia cratonic block. As a consequence, VMS deposits usually display strong deformation and thrusting, and their mineral and compositional zonation can be found overturned. Due to such common association between these deposits and terrane boundaries that reactivated during the Cenozoic, VMS deposits are especially susceptible to overprinting by later metallogenic processes, unrelated to VMS-producing

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