In this unit, we will explain the complexity of infrastructures and will challenge the traditional engineering perspective on infrastructures!
We will further explain why their behavior is often very difficult to understand and predict, and why we should consider them as complex systems.

This complexity lies in both the physical/technical and the social dimension, this is why we speak of socio-technical complexity. To mark the difference between this new perspective and traditional perspective we speak about infra-systems or infrastructural systems instead of infrastructures.