Since 1987 trade unions have been a key party to social partnership agreements in Ireland. Theoretical and empirical studies of corporatism point to positive outcomes for trade unions such as an increase in union density, ease of recognition, and increased employer support. However, apart from a modest increase in union membership numbers, none of these outcomes were realised. Union density levels have decreased significantly, union recognition is more problematic than ever, and employer opposition appears to have increased in scope and intensity. Decline in union density questions the capacity of unions to remain pivotal actors in the future. During the period of partnership union density in the private sector more than halved. It remains the paradox of partnership.