Methylammonium lead iodide has recently been recognised as an excellent photovoltaic material, with energy conversion efficient of up to 15% with the prospect of gaining higher efficiencies. The crystal structure shows phase transitions involving ordering of the orientation of the polar methyl ammonium molecular cation. Indeed, at room temperature there is still disorder of this ion. The only technique to give a complete structural description of the disorder in these phases is neutron total scattering coupled with the Reverse Monte Carlo method. We are proposing to apply this approach in the study of this important material.