This chapter highlights the potential anti-competitive risks raised by interlocking directorates between competitors (companies having common board members). Although in the US, Section 8 of the Clayton Act specifically prohibits interlocks among competitors, there is no such prohibition in Europe. The main claim of this chapter is that there may be an enforcement gap around anti-competitive effects of interlocking directorates in Europe. A review of relevant provisions shows that interlocking directorates are likely to fall short of EU competition law. In addition, national corporate laws, as well as tools of corporate governance may be of limited use to remedy competitive concerns. This chapter concludes with a discussion of research avenues that would inform suggestions for reforms.