Most of the professional training, thinking and strategies of architects, urban designers and planners, are strictly three-dimensional. In reality of course the city is four dimensional, and one needs to acknowledge the influence of time in planning and design strategies. Similarly, there has been relatively little analysis of the importance of interim, short-term or ‘meanwhile’ activities in urban areas. In an era of increasing pressure on scarce resources, we cannot wait for long-term solutions to vacancy or dereliction. Instead, we need to view temporary uses as increasingly legitimate and important in their own right. They can be a powerful tool through which we can drip-feed initiatives for incremental change – as and when we have the resources – while being guided by a loose-fit vision.