IUCN, as a neutral forum for objectively-based consensus seeking, is facing an ever-increasing demand to conduct independent scientific reviews of controversial development projects. As IUCN gains experience in conducting such processes, it is important to document which approaches lead to success and which ones cause problems, and to draw all these lessons into a more established methodology. This report examines IUCN’s handling of the process from the first contact with Sakhalin Energy in 2004 until the first meeting of the Western Gray Whale Advisory Panel in 2006, seeking to draw out the lessons from this experience so as to inform future practice.