A semiempirical method that yields accurate band gaps and atomic positions in sp(2)-hybridized, organic, semiconducting polymers has been obtained. This method is a tight-binding calculation where most of the parameters are determined via an ab initio local density approximation method leaving only pi-pi interactions to be adjusted empirically. Once fitted for one or two systems, the method can be applied to other similar systems without further adjustment. Accurate results have been demonstrated for a number of semiconducting polymers that contain C, S, N, and H.