The research question in this book is: How can an institutional perspective complement a functional perspective to understand the process underlying collective action in a mature eco-system? Rather than functionalist's viewpoint, this study adopts the perspective of organisational institutionalism. Standards share attributes with institutions, and that standard wars share attributes with processes of institutionalisation, where the processes connote the meaning of competition between different existing institutions and new ideas. The study focuses on the means by which focal firms succeed as institutional entrepreneurs in standard wars against competitors who have held leading and dominant positions in the previous institutional arrangements, resulting from victories in previous standard wars in the relevant technological field. The study demonstrates the importance of critical stakeholders and discursive activities. Further, it contributes the importance of the relevant practices used in a technological as well as organisational field, standard wars.