An expression for resonant molecular Raman scattering in terms of the complex electric-dipole polarizability tensor is presented and implemented with first principles complex polarization propagator theory. The theory reveals the strong role of phase delays of the detected Raman radiation in the resonant case. Application on gaseous nitrogen predicts a Raman scattering enhancement of circa 104 in the resonance regions of the b(1)Pi(u) and b '(1)Sigma(+)(u) states as compared to the nonresonant case. (C) 2008 Elsevier B. V. All rights reserved.