There has been significant interest in the oxide ion conducting material La2Mo2O9 as a new electrolyte after initial reports of conductivity as high as that of YSZ at lower temperatures. Recently it has become apparent that there are discrepancies in the conductivity data reported in the literature, with some observing a large jump at the alpha-beta phase transition temperature, whilst others report only a minor slope change. To date there have been no clear indications of why there are these discrepancies. There have also been no direct measurements of crystal structure and conductivity in-situ that would help resolve this issue. It is the intention of this work to develop an understanding of this feature of this material.