The topics of leadership style and organizational culture have attracted considerable interest from different researchers in various settings, including the academia and practitioners. And the two variables have demonstrated their superiority in making organizations achieve their goals. The practice of certain leadership styles over others combined with culture types that increase the cooperation between subordinates and employers has revealed tremendous impact on organizational performance. While the link between leadership and performance, and between culture and performance has been scrutinized independently, very little has been published regarding the link between the three concepts based on a single study. And no book has been published to show how the leader¿s style and the culture of an organisation, taken together, impacts business performance and success, with an application to the ever-growing industry of mobile telecommunication. The role of this book is to establish that link, through empirical evidence, and it comes up with the conclusion that the interplay of some leadership styles and some organisational cultures impacts business performance.