Reflexive monitoring is an evaluation method that gives urban practitioners insight into the progress of their project in real time. It helps them evaluate day- to-day activities and to respond to them while considering the bigger picture.This is especially helpful when addressing the complex challenges nature-based solutions tend to combat, such as climate change and social exclusion. A six-step procedure has been developed to implement the reflexive monitoring process. The process is supported by seven reflexive monitoring tools which may be applied by urban practitioners. This guidebook presents a brief description of these steps, tools and examples of how the Connecting Nature cities applied them.