The effect of discontinuous stainless steel fibers (diameter 60 mum) as an admixture in cement paste on the thermoelectric behavior (the Seebeck effect) was systematically studied as a function of fiber volume fraction from 0 to 0.50 vol%. Without fibers, cement paste has an absolute thermoelectric power of +3 muV/degreesC. A fiber content of up to 0.20 vol% makes the absolute thermoelectric power more negative (down to -63 muV/degreesC), whereas a fiber content of 0.20-0.50 vol% makes the absolute thermoelectric power more positive ( up to +31 muV/degreesC)-even more positive than the positive value for the steel fiber by itself (+8 muV/degreesC). The value is zero at a steel fiber content of 0.27 vol%. The effects are probably due to carrier scattering rather than conduction. (C) 2004 Kluwer Academic Publishers.