An important early step in any planned remote-sensing experiment is an analysis of the information content of the equations which will ultimately be inverted. In this paper, we employ the singular function theory, which is the natural framework within which to discuss the analysis of first kind Fredholm integral equations. Using this theory, we are able to fully analyze the information available from an aerosol extinction experiment. It is important to appreciate that this information is actually of two forms: first, the number of pieces of information available for a given experimental error level, and second, the type (or location) of this information. To fully appreciate the latter, we apply this theory to the inversion of eleven synthetic data sets, including three multimodal model size distributions.