Humanitarian aid is a significant and growing dimension of Official Development Assistance (ODA). Meeting humanitarian needs caused by natural disasters or armed conflicts poses serious challenges for donors financing humanitarian action. Reforms to improve effectiveness and efficiency of humanitarian action are underway. The Principles and Good Practice of Humanitarian Donorship (GHD), endorsed in 2003 by 16 DAC governments and the European Commission, provides an opportunity for harmonising donor practice in this field. The DAC has agreed to take an active role in promoting GHD and since 2004, a GHD assessment framework has been applied in six Peer Reviews (Australia, Belgium, Germany, Norway, Sweden and Switzerland). This document summarises the findings and experience with the aim of assessing the usefulness of this approach.