Computer simulation techniques are used to model the structures of several Aurivillius phases (with the general formula (Bi2O2)[A(m-1)(B)(m)O3m+1]) and related compounds. The methods are based upon interatomic potentials and efficient energy minimisation procedures. The results indicate general agreement between the simulated and experimental structures. From recent diffraction data of the Bi2GeO5 system, a new refinement of the crystal structure has been obtained. A discussion of trends related to the Bi lone-pair parameters of these Aurivillius phases is also presented.