This paper investigates the effect of CEO succession on the performance of family firms characterized by collegial leadership and the moderating role of the Family CEO, of the board of directors and by the size of the firm. The empirical analysis, carried out on a sample of Italian family firms for the years 2012-2016, shows a positive effect of succession on the performance of family businesses with shared leadership. Moreover, this relationship is negatively moderated by the composition of the co-leadership structure, the characteristics of the board of directors and the size of the firm.