The Variscan front of NW Europe has been drawn in the past from Belgium across southern England and southern Wales towards southern Ireland but the term Variscan front is not well defined and means different things to different people. A tectonic front should represent the outcrop of a frontal thrust or the tip line of the basal detachment. In fact such a tectonic front cannot be traced along the so-called Variscan front in Ireland. Field-based studies of the western part of the Irish Variscides show that the fold-and-thrust belt continues north of the so-called Variscan front but deformation decreases gradually. Therefore we suggest, supported by seismic data, a detachment which ends as a blind thrust far to the north. The tip line of this basal detachment represents the true tectonic front of the Variscides in SW Ireland. Shear indicators show locally a dextral shear component near major faults and 3D-microstructural strain analyses show varying X-axes and oblate deformation indicating transpression during the tectonic evolution of the western Irish Variscides. Therefore a thin-skinned model associated with dextral shearing and transpression in the hanging wall of the basal detachment is suggested. The evolution of the Variscan fold-and-thrust belt in NW Europe is related to the West European indentation model but also to pre-Variscan basement structures as the Leinster-Wales and London-Brabant massifs. Finally, an attempt is made to outline the Variscan front along the entire NW European Rhenohercynian fold-and-thrust belt (FTB).