The chapter starts from the premise that peaceful change can only be regarded as peaceful if it is founded on the shared understanding that the change being instituted is “good” – meaning that it is not incompatible with the vision of the “good life” of those who will be touched by the change. The chapter uses constructivist insights to establish if international organizations can be seen as agents of peaceful change, and if so, how and with what opportunities and limitations they are able to undertake action that can lead to peaceful change? The chapter focuses – perhaps counterintuitively – on NATO as an agent of peaceful change, demonstrating that even though NATO is widely perceived as an agent of repressive – even violent change – it has played an important role as an agent of peaceful change in the relations of its members and within the liberal international order. However, the chapter finds that the prospects of international organizations acting as agents of peaceful change outside their own domain are hampered by them being “sticky” and more likely to be guardians of the status quo rather than agents of change.