This chapter describes the agile transformation of an IT organization in China with about 4000 people including contractors. In the span of one year, 47 teams and 1700 engineers moved from traditional to agile way of working. There was a 44% reduction in development lead-time, 5% reduction in production defects and 22% reduction in production incidents. This agile transformation occurred at two levels. At the organization level, adoption speed was crucial, as we wanted to reach critical mass in rapid time with limited coaching resources. This was very much an entrepreneur startup problem, where customers in our case are teams and members in the IT organization. At the team level, a practice architecture provided a roadmap for continuous improvement. A theory-based-software-engineering approach facilitated deeper learning. Beyond the usual factors for leading successful change, this transformation exemplified the use of a startup mentality, social networks, practice architecture, simulation, gamification, and more importantly integrating theory and practice.