We examine the role of organized labour in the restructuring experience of two coal-mining regions in the 1990s. Under similar external circumstances, the Czech Republic’s Ostrava region underwent gradual restructuring from early on whereas Romania’s Jiu Valley region went through no restructuring until 1997 followed by massive layoffs over 2 years. We conduct a quantitative exercise that accounts for mine productivity, labour market conditions and the constraints in compensating laid-off miners. We show that the Jiu Valley’s delay in restructuring was inefficient. Gradual restructuring with compensation would have benefited both the miners and the government. The proximate reason for the delay was the Jiu Valley miners’ action against restructuring. We discuss what motivated their action and why it was effective.