Innovation platforms are new collaborative organisations in the urban development context that aim to support innovation. They assemble different organisations and actors and act as flexible intermediary links between the same. By being intrinsically flexible and adaptable in form and function, the innovation platform can be seen as an organisational accomplishment or enactment of adaptive planning. Central to adaptive planning is the balance between organisational flexibility and stability, which is also intrinsic to any public innovation work. Public sector innovations are often perceived to require open and experimental trial and error strategies – while their institutional setting simultaneously requires stability. The aim of this article is to analyse how individuals working in innovation platforms make sense of their organisation at the intersection of adaptability and stability. We describe the tension between adaptability and stability inherent to innovation platforms, as the platforms are set to facilitate relationships between actors while maintaining their role as an independent organisation. This article is based on an in-depth multiple-case study of 15 innovation platforms in the Nordic countries, consisting of interviews with representatives, as well as extensive desktop material and participant observations. By adopting an organisational and sense-making perspective, we analyse how people working in platforms enact their organisations and their environment through processes of belief and action-driven sense-making. We conclude that despite innovation platforms’ strong advocacy – and sense-making – in terms of adaptability and chameleon-like characteristics, stability is enacted through making sense of themselves as a legitimate and necessary position/node in urban planning and development.