The central Transantarctic Mountains of Antarctica are divided into distinct lithotectonic packages of variable age, deformation style and metamorphic character. In the Miller Range (83°S, 155°E), the boundary between two such lithotectonic units is a low-angle, thrust-type ductile shear zone that carried high-grade gneisses of the East Antarctic craton to the southeast over a lower-grade metasedimentary sequence. Broad constraints limit the age of ductile deformation as late Early Proterozoic to Late Cambrian. In addition to a reverse component of movement, this zone also records along-strike motions in a direction subparallel to the present orientation of dominant Beardmore- and Ross-age orogenic trends. We postulate that major pre-Ordovician crustal shortening which occurred along this part of the Gondwana continental margin began in the Middle to Late Proterozoic as an early phase of long-lived convergence. Furthermore, orogen-parallel displacements indicate that oblique plate interactions may have played an important role in the early evolution of this active margin.