Neutron total scattering data for alpha-Bi2O3 and delta-Bi2O3, considering both the Bragg and diffuse components, have been analysed by the reverse Monte Carlo (RMC) method to extract experimental information concerning the short-range correlations between pairs of ions. These results complement the average structural information provided by conventional Rietveld refinement of the Bragg scattering alone. The radial and angular distribution functions in the stable ambient temperature alpha phase and superionic delta phase of Bi2O3 are presented and compared with the corresponding data for the metastable beta phase reported previously. These data provide an important insight into the nature of the anion disorder within the highly conducting delta phase and the relationship between the delta phase and its ordered alpha and beta counterparts. (C) 2010 Elsevier B.V. All rights reserved,