The transition from nuclear power generation to decommissioning carries a number of safety challenges tied to human and organisational factors. This report discusses these challenges and brings together the experiences of members of the NEA Working Group on Human and Organisational Factors. It includes an overview and topical case studies from global decommissioning activities and sums up the good practices and lessons learnt to help organisations in their own endeavours to decommission nuclear installations. This report can be used as a guide for self-assessment for both licensee organisations and regulatory bodies to manage the human and organisation factors in the various phases of their decommissioning activities.