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The Displacive Compensation of Porosity method for fabricating dense, shaped ceramic/metal composites at modest temperatures is demonstrated. In this process, liquid-metal/ solid-ceramic displacement reactions are used to generate more ceramic (by volume) than is consumed, so that pores within a ceramic preform can be filled with the new ceramic phase (i.e., densification without sintering). Dense, lightweight MgO/Mg-Al composites (74-86 vol% oxide) and higher-melting, co-continuous MgAl 2 O 4 /Fe-Ni-Albearing composites (42-59 vol% oxide) have been produced via the pressureless infiltration and reaction of magnesiumbearing liquids with porous preforms of Al 2 O 3 and NiAl 2 O 4 +Fe, respectively, at temperatures of 900°-1000°C. The composites are relatively tough and retain the shapes and dimensions (to within a few percent) of the starting preforms.