An understanding of the overall nanocomposite behaviour is developed through the combination of real data from micro/nanostructures and the fundamental material characteristics of the constitutive phases. Captured morphological images, using either scanning electron microscopy (SEM) or transmission electron microscopy (TEM), are utilised to generate the geometric information regarding mapping the micro/nanostructures. The material Properties, on the other hand, are obtained from conducted tests and previous literature. The numerical results predicting the elastic moduli of polypropylene (PP)/clay nanocomposites are compared with the experimental data and available composites theoretical models. Very good agreement has been shown, establishing the viability of this kind of morphology-based numerical approach. (C) 2009 Elsevier Ltd. All rights reserved.