Fulfilling the potential of Agile development depends on people truly wanting to change how they work. Transitioning to new methods of development is particularly daunting in a large organization that already has a sizeable existing code base and a broad set of existing customers. In our experience, development teams tend to reach a plateau implementing a subset of Agile practices, and those tend to be generally focused on the planning and iterative aspects of Agile. This paper describes our experience in overcoming the barriers to increasing the adoption of Agile practices. Drawing from Agile principles, we have developed an approach for improvement that enables teams to accelerate change, deepen their degree of understanding, and increase their success in execution. We have found this helps teams to overcome the plateau effect.