To what extent is labour mobility in the European Union a threat to the strength of unions? We argue that the combination of cheap labour, workforce heterogeneity, and low unionization among labour immigrants' is a potential challenge for unions. The challenge will be particularly severe if...

We develop a simple framework to show the effects of trade cost reduction on unionized wage, employment and domestic welfare when a domestic firm strategically chooses the amount of formal in-house production and subcontracting to the informal sector. We show that a lower trade cost increases...