The article addresses international campaigning for labour rights and global labour networking against illegitimate labour practices of global corporations. Theoretically, the article offers an analytical framework to explain and strategise labour empowerment and disempowerment in Global Production Networks. The problem is approached by reviewing how the issue of labour agency is addressed in literature about Global Value Chains, Global Production Networks and Labour Geography. Given the limited progress in theorising cross-border labour agency, two new approaches within the industrial relations research tradition – Strategic Union Corporate Analysis and Strategic Choice Framework – are linked to economic geography perspectives, with a view to offering a more integrated Global Labour Network (GLN) approach. The framework is then applied to analyse and explain the outcome and impact of a Danish–Malaysian campaign in support of a worker collective in a Danish controlled joint venture in Malaysia struggling for union recognition and collective bargaining agreement. The article concludes that the GLN approach integrates the achievements of the labour agency literatures by focusing on explaining changes in strategic labour power from the dynamic interface of strategic opportunities and labour capacity. Moreover, it is argued that semi-comprehensive international campaigns of labour NGOs may add critical but insufficient support to labour agency in developing countries with highly legalistic and politically infused industrial relations systems. Finally, international labour NGO networks will not be sustainable if they are not integrated with and supported by national and global union networks that match the power of global corporate networks.