How do organisations typically adopt open source? This can be described as a path which starts with denial that open source is relevant and ends with leadership as a competent open source player. Most organisations will find themselves somewhere in between. It is desirable to advance on this path to unlock the full potential of the open source model and the value it can create. In this presentation we will look at a five stage model which helps to understand the path of open source adoption and gives concrete steps how to advance through the different stages. It helps corporations to identify what needs to be done to mature in using and contributing to open source. It also helps open source communities to understand what corporations need from open source so mutually beneficial practices can be established. We will look at where the model is coming from, how it can be applied, and discuss some examples and lessons learned.