Polysulphone of bisphenol A (PSU)/acrylonitrile-butadiene-styrene (ABS) blends have been obtained by direct injection moulding at different temperatures and for compositions in the PSU-rich range. Direct injection moulding provided a mixing level similar to that of kneading. The blends were almost fully immiscible with the exception of the polybutadiene (PBD) phase where some PSU appeared to be present. Only a very small amount of ABS was required to greatly improve the tracking index of PSU. The mechanical properties, however, were those of a compatible material, and did not depend on the injection temperature. Moreover, with the exception of the ductility, they were in fairly good proportion to the blend composition, and provided the most balanced set of properties at an ABS content near 5%.