Seen in the context of previous studies on oxygen ion conductors, and Bi-based materials in particular, our results further consolidate the state of mechanistic understanding of the conduction processes, while also adding local-level insights regarding structure and dynamics. Firstly, conduction in the V-substituted materials appears to operate in a similar fashion to Bi 26 Mo 10 O 69 , with rapid localised rotation measured for dopant polyhedra at low temperatures preceding the onset of long-range, isotropic conduction via cooperative exchange with the Bi-containing sublattice at higher temperatures. However, in the Bi 26 Mo 10 O 69 system the onset of sublattice exchange appears correlated with and possibly driven by a monoclinic-triclinic phase transition at 583 K, in contrast to the temperature-invariant structures of the vanadates and phosphates studied here.