The method of positron emission particle tracking (PEPT) has been adapted for use during extrusion. A particle 2 mm in diameter was tracked through a 45 degrees conical die geometry using ram speeds of 5 and 10 mm min(-1). The particle was placed at different points across the diameter of the barrel in order to determine the dependence of the speed and strain rate on the initial position. Analysis of the speed of the particle during extrusion showed that the clay based paste used in the experiment exhibited plug flow in the barrel and the die land regions. The maximum extensional strain rate was shown to be independent of the ram speed, whereas the shear strain rate at the wall was highly dependent on the ram speed.