This paper investigates why some attempts at pacted transitions from non-democratic rule fail, while others succeed. It determines the composition of opposition organizations that enable pacting. The paper draws on a data set compiled by the author comparing forty-five attempts at negotiations. The QCA analysis shows that only those negotiations that include the opposition with strong organizational capacity succeed and end up with democratization. This strong organizational power of the opposition can be drawn from trade unions or The Catholic Church participating in negotiations, even if the initial regime is personalistic.