The paper suggests a new method of transiting from Traditional Software Development (TSD) to Agile Software Development (ASD) called non-disruptive transition. The novelty of the method consists of allowing to complete the major transition steps to the agile “mindset” while remaining in the frame of an already established TSD process. The method is being developed using a knowledge transformation perspective to identify the main features of ASD mindset and how it differs from the one of TSD. More specifically, it uses a version of Nonako’s SECI model to represent software development. To analyze the current mindset and plan the movement to the mindset that is more agile, the paper suggests using a process modelling technique that considers the software development process as a complex socio-technical system. The paper also discusses external conditions that might hinder going all the way to becoming agile and require the transition to stop, and how to become agile while developing complex systems.