The linear polarizabilities and first hyperpolarizabilities of two geometrical isomers (Z, E) of donor-acceptor azo-enaminones have been calculated, taking into account frequency dispersion effects, through CPHF method. Static results were also obtained at the MP2 level and correlated dynamic values were estimated using the multiplicative correction scheme. Our results show that the diagonal component of the first hypepolarizability of E isomers is enhanced with increasing donor strength. Dispersion effects have a marked influence for the standard frequencies considered here (omega = 0.0239 and 0.0428 a.u), specially for second harmonic generation. (c) 2007 Elsevier B.V. All rights reserved.