This paper considers the effective properties of cellular materials. The present approach and some earlier proposed methods are compared and discussed. The main effort is placed upon the continuum mechanics approaches' ability to predict effective elastic properties. It is shown that two methods are distinctly better, namely a slight modification of the Mori-Tanaka approach and a new approach by Dvorak and Srinivas, which is shown to predict the Young's modulus and shear modulus of the Divinycell H-grade PVC foam almost exactly.