Building on the framework developed in Chapter 2, this chapter looks specifically at the factors shaping the persuasive impact of conflict warnings articulated from within selected Western states and IOs, as opposed to warnings from outside sources such as NGOs or news media discussed in Chapters 4 and 5. The chapter is based on a ‘best-case design’ by focusing on six actors – three states and three IOs – all of which have made a clear and strong commitment to conflict prevention and preventive action by policy or mandate. These are the United States, the United Kingdom and Germany and the UN, the EU and the OSCE. We identify the most important factors or combination of factors, but also investigate differences between the six foreign policy systems as well as between types of actors, especially, states and international organisations. We found that their relationships and roles are often more fluid than that and both are affected by broader factors such as pre-existent policies, shared diagnostic beliefs or organisational cultures.