The western Tauern Window of the Eastern Alps constitutes a mature transpressive wrench zone generated by Oligocene-Miocene convergence between the Dolomites Indenter and the European foreland. As a major structural divide, it translates convergence-parallel north-south shortening into convergence-perpendicular eastward lateral extrusion. About 7000 foliation, lineation, fold-axis, axial-plane, shear-zone, and shear-band measurements at ~1800 sites detail the structural geometry and evolution during indentation and transpression, modeled by numerical and analogue-material experiments. The results outline the western Tauern Window as an orogen-scale zone of localized deformation, consisting of tight, upright folds, reactivated by a sinistral shear-zone network. It connects the Giudicarie Belt southwest of the indenter salient with the Salzach-Ennstal-Mariazell-Puchberg Fault (SEMP) in the northeast. This transpressive zone has a sigmoidal vortex geometry, decoupling the Ötztal Basement in the west from the extruding wedges of the Eastern Alps in the east. Shortening was successively absorbed by nappe stacking, upright folding, and dome formation and then maintained by transpressional shearing that led to lateral extrusion, probably promoted by a change in the lithospheric configuration. The western part of the SEMP likely rotated ≥20° clockwise around a pole approximately halfway along its entire length during the indentation.