Macroions in solution have been studied by a variety of physicochemical methods. In particular, small angle neutron scattering (SANS) and light scattering (LS) have been widely used in this domain (e.g., micelles, emulsions, proteins) because of the wealth of information these techniques can provide. We describe here a method by which both single particle and interparticle structure factors [P(Q) and S(Q), respectively] can be extracted from SANS data. P(Q) is given by the SANS data under conditions of low concentration and moderately high ionic strength where interactions between macroions are negligible. For conditions where the interactions are important and in the Q region covered by SANS, S(Q) can be deduced by dividing the intensity distribution by P(Q) obtained previously. If available, the LS data further provides the osmotic compressibilty so that the values of S(Q) at vanishing Q’s can be interpolated.