In conventional thermoelectric materials (Bi2Te3, PbTe, SiGe), the conduction and valence bands are derived from s and p orbitals. But most thermocouple wire materials (chromel, alumel, WRe, PtRh) involve alloys with partially filled d-bands, resulting in Seebeck values much larger than for metals with filled or empty d-bands (such as Cu or Na, respectively). Semiconductors for which the valence and/or conduction band are dominated by d-band character may be able to combine the high Seebeck values typical of transition metal alloys, with the ability to achieve optimum doping levels typical of conventional thermoelectric materials. Certain metal-silicon compounds appear to have this desirable combination of properties. In this paper, compounds of silicon with elements from groups 1 through 8, including the d-band elements, are reviewed for their potential as high figure of merit (ZT) thermoelectric materials. A number of amateirials are identified which appear to have the potential for ZT values much greater than ZT ~ 1 typical of current state of the art materials.