The essay addresses the question of labor market reform and union responses to market-oriented structural adjustment programs in two small open economies in the Southern Hemisphere. The leading questions are whether ideological militancy and unity or other factors matter when it comes to the labor movement’s ability to confront the challenges of market-oriented reform projects undertaken by new and well established democratic regimes. Political regime change and the history of interest group intermediation systems and labor market dynamics before and after the shift from state to market-oriented economies are reviewed in order to evaluate the data pertinent to each case. We conclude with some general comparisons and an argument in favor of the institutions and ideology thesis.