The linear polarizability, alpha, the first hyperpolarizability, beta, and the second hyperpolarizability, gamma, of three different classes of basic heterocyclic organic structures have been calculated by the ab inio time-dependent coupled Hartree-Fock-Roothaan method using a 4-31G basis set augmented by diffuse p and d functions. For the alpha and gamma coefficients, the calculated orders thiophene > pyrrole > furan for the five-membered rings; pyridine > pyrazole > s-triazine for the aromatic bases; and benzothiazole, oxazole for the fused ring systems show a qualitative relationship with the corresponding order in Delta epsilon(HOMO-LUMO) of the respective group of molecules. The beta values do not appear to show a discernible trend. The dispersion of alpha(-omega;omega) and those of gamma(-omega;0,0,omega), gamma(-omega;omega,omega,-omega), gamma(-2 omega;0,omega,omega), and gamma(-3 omega;omega,omega,omega) in the case of the five-membered rings are also reported.