UK food retailers have become arguably one of the most important drivers for change in beginning to create more sustainable supply chains.   This is now no longer just a reputational issue but is based on concerns for food security and is clearly a competitive issue.  Rethinking waste as resources and the need to  make step changes on operational energy use has encouraged retailers to move from corporate targets that are doable to those which can only be classified as BHAGs and are beyond current knowledge on how to achieve them.