The metastable excited statea(1)[3&Sgr;+]of PbO is proposed as a candidate system in which to search for an electron electric dipole moment (EDM). It is shown that the sensitivity to an electron EDM(de)could reach10−31 e⋅cm—an improvement of>104over the current limit. Observation of an electron EDM would provide definitive evidence for physics beyond the standard model, and many currently favored theories predict|de|>10−31.The sensitivity of the proposed technique arises from a combination of several unique properties of PbO, which simultaneously provide a large EDM enhancement factor, narrow magnetic resonance lines, and high counting rates. The structure of the nearly degenerate &OHgr;-doublet system in PbO permits the use of unique and powerful techniques for the rejection of systematic effects. ©2001 American Institute of Physics.