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In the southern Apennines fold-and-thrust belt, thermal indicators record exhumation of sedimentary units from depths locally in excess of 5 km. The thrust belt is made of allochthonous sedimentary units that overlie a 6-8-km-thick, carbonate footwall succession. The latter, continuous with the foreland Apulian Platform, is deformed by reverse faults involving the underlying basement. Therefore, a switch from thin-skinned to thick-skinned thrusting occurred as the Apulian Platform carbonates--and the underlying thick continental lithosphere--were deformed during the latest shortening stages. Apatite fission track data, showing cooling ages ranging between 9.2 [+ or -] 1.0 and 1.5 [+ or -] 0.8 Ma, indicate that exhumation marks these late tectonic stages, probably initiating with the buttressing of the allochthonous wedge against the western margin of the Apulian Platform. Pliocene-Pleistocene foreland advancing of the allochthonous units exceeds the total amount of slip that, based on cross-section balancing and restoration, could be transferred to the base of the allochthon from the underlying thick-skinned structures. This suggests that emplacement of the allochthon above the western portion of the Apulian Platform carbonates was followed by gravitational readjustments within the allochthonous wedge, coeval--and partly associated with--thick-skinned shortening at depth. The related denudation processes are interpreted to have played a primary role in tectonic exhumation. Keywords: low-temperature thermochronology, thin-skinned thrusting, thick-skinned thrusting, gravitational instability, extensional faulting.