This paper critically discusses a time-honored thesis in the social science literature, i.e. that membership control over union policy is undesirable due to its potentially adverse effects on third parties and/or society as a whole. Based on extensive field research in Italy, the paper first analyzes in general terms and then illustrates empirically two scenarios in which the presence of procedures which both involve the rank-and-file workers and give them ultimate decision-making power is not only compatible but even conducive to "responsible" union behavior while their absence leads to opposite outcomes. In particular, the paper argues that the absence of systematic mechanisms (like a vote) for ascertaining the workers' preferences may alter the internal balance of power within trade unions in favor of factions pursuing more militant agendas and that when deliberative mechanisms are at play, "democratic" procedures may lead to internalization of third parties' legitimate interests even when workers have more extreme preferences than their leaders. The two empirical illustrations examine the relationship between centralized bargaining agreements and decision-making-procedures in Italy and the trade-offs facing the employees of two matched-paired factories in the Mezzogiorno, respectively.