The use of externally imposed electric fields is shown to activate self-propagating solid-state reactions. Experimental observations and modeling studies show different field effects, depending on the relative electrical conductivity of the product of the synthesis reaction. In systems with relatively nonconducting products the reaction wave propagates in a steady-state mode. Examples of the influence of the field on the mechanism of solid state reactions are provided for the synthesis of tungsten silicides and AlN-SiC composites.