Characterization of small particles ubiquitously involves scattering measurements at multiple wavelengths or at multiple angles. Such measurements are desired to provide the maximum amount of information regarding the particles. This paper develops a method to analyze the information content of scattering measurements when applied to characterize the shape and size distribution function of spheroidal particles. For a specific application. this method enables the selection of the optimal set of conditions (in terms of the wavelengths and the scattering angles) to perform the scattering measurements. Numerical simulations have demonstrated that this method can significantly improve the determination of the shape and size distribution function of spheroidal particles based on multispectral scattering measurements. The results obtained here provide valuable insights into the optimal design of techniques and instruments for particle characterization using scattering measurements. (C) 2008 Elsevier Ltd. All rights reserved.