XD™synthesis, powder blending and hot pressing techniques have been utilized to produce NiAl composites containing 4, 7.5, 15 and 25 vol% alumina whiskers and hybrid composite materials with 15 vol% Al2O3+ 10 or 20 vol%, nominally 1μm TiB2particles. The resistance to slow plastic flow was determined at 1200 and 1300 K via compression testing in air under constant velocity conditions. The stress-strain behaviour of the intermetallic composites depended on the fraction of second phases where the 4 and 7.5% Al2O2materials flowed at a nominally constant stress after about 2% deformation, while all the other composites exhibited diffuse yielding followed by strain softening. The flow stress-strain rate properties increased with volume fraction of Al2O3whiskers except for the 4 and 7.5% materials, which had similar strengths. The hybrid composite NiAl + 15Al2O3+ 10TiB2was substantially stronger than the materials simply containing alumina. Deformation in these composites can be described by the Kelly and Street model of creep in perfectly bonded, rigid, discontinuous fibre materials.