Any sustainable conservation process for stone monuments is directly dependent on the durability of this material. The study of stone deterioration proposed on a partnership basis by a research group from Blaise Pascal University, Clermont-Ferrand, France, is therefore one which is of interest to all national and international teams operating at Angkor. The ICC recommends that this study project be given final approval. It will focus on Ta Keo Temple and extend over a four-year period (2006-2009). An appeal for contributions is hereby launched, and each team is asked to kindly take the matter up with any donors and/or laboratories that may be interested in this study theme.