Why would European unions, in countries with greater union density, seek support from American unions who are struggling to retain power and influence? Why would Change To Win (CTW), an upstart union confederation, expend its limited resources supporting the European labour movement? These questions motivate this paper that analyses the activities of CTWs European Organizing Center and its partner unions. The paper uses the diffusion literature to argue that CTW and its partners have developed a common sense of the problems facing unions globally, and solutions rooted in specific organizing practices and broad power resources, abstracted and adopted to varying local contexts. The paper further argues that this North-North collaboration constitutes a new form of labour internationalism through the intentional diffusion of organizational strategy and that US unions bring a particular set of power resources to these cross-Atlantic relationship resources born of the more advanced version of neoliberalism found in the United States. 'All the unions in Europe and the world actually have the same problems now (Interview, European partner union representative 12, March 15 2017)'. Why would European unions, in countries with union density ranging from 25 per cent to over 80 per cent, seek support from American unions who are struggling to keep a toe-hold? Why would Change to Win (CTW), an upstart