This paper describes the application of the numerical solution of the Percus–Yevick approximation for a multicomponent system of sticky hard spheres to small angle x-ray scattering experiments. The effect of polydispersity on the pair correlation function is quantitatively described, thus enabling the analysis of experimental data. In this way quantitative estimates of the size distribution width, interaction radii and the measure of attraction between particles can be obtained. The attractive interaction in a system of sticky spheres is known to give rise to a transition analogous to a gas–liquid phase transition. The effect of polydispersity on this transition is discussed. Finally it is shown how the model can be used to describe small angle x-ray scattering from an AOT microemulsion system.