Since 2014, the United States has publicly accused Russia of violating the Intermediate-Range Nuclear Forces (INF) Treaty, a landmark Cold War nuclear arms control agreement. On February 14, 2017 the New York Times reported that Russia has already deployed a significant number of prohibited missiles. In light of these developments, the Trump administration will face the tough decision about whether or not to remain committed to the treaty. This article by Ulrich Kühn and Anna Péczeli recounts the history of the INF treaty and assesses Russian and US interests related to the treaty. It develops three possible future scenarios for Russian actions and their impact on, as well as possible responses by, the United States and its NATO allies. The conclusion is that NATO allies will most likely face an ambiguous Russian stance with respect to INF weapons, which will make it difficult to find a balanced response strategy, bringing together diplomatic and economic pressure as well as military means to respond to Russia’s INF violation.