Europe’s security situation has evolved somewhat over the past few years, causing national defence policies to be reviewed and strengthened. Being members of Nato and the European Union, the Benelux countries of the Netherlands, Belgium, and Luxembourg have been changing their defence policies to face complex military and non-military threats. The potential threat from Russia is one factor which has been behind their closer military cooperation, supported by the process of rebuilding national military capabilities. Progress has been especially visible after 2014 most especially due to Russian aggression against Ukraine, along with hybrid threats and terrorists attacks. All three countries tend to cooperate with each other while also enjoying ever-closer relations with Nato and other EU members, while the USA has a special place in this arrangement. All of these connections and areas of cooperation will be covered in this article. The author utilises the qualitative research approach which involves one or more case studies, along with institutional and behavioural analysis, deskbound research, analysis, and synthesis methods.