Experimentation happens mostly in urban living labs but can be used outside a lab environment. It comprises the idea of time-limited interventions with the ambition of learning different possible solutions or outcomes. With experiments we do not mean those as in natural sciences; they should be understood as a more explorative and tentative practice, characterised by dedicated reflection moments. An experiment can be defined by local authorities, by stakeholders of an area or in co-creation processes. The ‘what if’ question at the start of an experiment is an interesting framing and focusing amoment – for example, ‘What if we used a mobile meeting point in a street?’
The Antwerp citylab2050 used experiments in an urban lab called ‘garden streets’, in which neighbours and design teams experimented with a mobile meeting place (on wheels) that could be rolled out into a street.  In another lab citizens experimented with rain barrels on the street as DIY (do-it-yourself) water retention buffers, where the water could be used for urban plants. The barrel was hidden in a planter for aesthetic reasons and police regulation.