Reflexivity is the sixth colour on IDEAN‘s ‚rainbow‘ of general principles. It relates to self-knowledge and self-awareness promoting the capacity of a system (and its components) in order to reflect its own status and learn and plan for change. Neighbourhoods are complex and self-organised arrangements featuring diverse components, dynamic processes, multiple scales, and differing interests. IDEAN cultivates the capacity for individual neighbourhoods to reflect their own situation through self-inquiry and collective learning as an essential prerequisite to development and adaptation, including modern sensing and crowd sourcing techniques.