How do parties adapt to an environment characterised by the rejection of intermediate bodies? They both offer members more opportunity for direct and online participation and strengthen their leadership. By proposing an innovative framework for the analysis of disintermediation in politics, and through an in-depth examination of the inner workings of two Italian parties (the Partito Democratico and the Movimento 5 Stelle), this book shows both how these trends are connected and the ways in which the promise of unmediated intra-party relationships lead to the emergence of new forms of intermediation.