Cu2ZnSnS4 (CZTS) is a solar cell material of great interest. However the material when fabricated, although of high symmetry, contains substantial defect concentration and a high degree of atomic mixing on different crystallographic sites. A lack of knowledge regarding the structure is currently hampering progress on this material. X-ray measurements have shown anion displacement changes begin around 420 K with a phase transition between the low-temperature kesterite structure and a high-temperature sphalerite structure at 1149 K. In the region 1136-1161 K a two-phase region occurs with both phases coexisting around the first order phase transition. We propose to undertake high-resolution neutron powder diffraction study to fully characterise the material from 4 K to 1200 K using HRPD.