Improved conceptualising of hybrid interference below the threshold of armed conflict

European policymakers have identified the need to understand influence operations on social media, cyber-attacks or hidden economic investments – activities that can be characterised as hybrid threats or hybrid warfare. Yet, the difference between hybrid threats and hybrid warfare is unclear. In 2019, Mikael Wigell therefore coined the term “hybrid interference” to clarify the distinction between “hybrid warfare” and “hybrid threats”. However, less attention has been given to the activities hybrid interference may consist of. To address this gap we have used a morphological analysis, which is a structured tool for analysis that addresses all aspects of a concept. Through this method, we propose categories that make more sense of the complex phenomenon of hybrid interference. These five categories are international politics, coercive diplomacy, priming, covert coercion, and sabotage and assassinations. This article also identifies problems with referring to activities in the category of international politics as hybrid interference activities. The result is novel because we place all combinations of tools and methods within the concept of hybrid interferences in one of the five above-mentioned categories, and as such have provided a detailed operationalising of the concept in a transparent manner.