Successful software development projects depend, among other things, on their project manager’s leadership capabilities. This paper analyzes how specific leadership styles of IT project managers contributed to the success of a large IT project realized by an IT service provider in India. We conducted an interpretive case study following the principles of the Grounded Theory Methodology to explore whether there are special leadership characteristics in a software development project in a typical offshore context in India, and their potential contribution to IT project success. The core concept of leadership as a key management issue emerged from the interpretive approach of our study, with ‘collaborative leadership’ and ‘directive leadership’ as the two most relevant characteristics of the IT project managers. We show how the use and the right balance of these two leadership styles help in overcoming the problems induced by different quality expectations between client and vendor. We also show why IT expertise is important to execute these two primary leadership styles, and how IT leadership contributes to the successful management of large software development projects.