The circular economy is a muchdiscussed topic. In recent years it became clear that scarcity of resources, pollution and landfill will make circularity inevitable in the near future.To achieve this major changes should be made in the built environment and the building sector, as the built environment is currently mostly organized in a linear way. This report describes the steps that need to be taken to reach a circular economy, and identifies the main challenges. It is possible to start building more circular already at this moment, but full circularity cannot be guaranteed until the whole market behaves circular. Contracts can play a role to guide the market in this direction by incorporating take or buy back guarantees and maintenance components to create incentives for circularity. Lease or integrated contracts might be the best options to achieve this, but in general all contracts can be used to achieve the first steps to circularity.

A circular economy has gained attention as a potential solution to the tension between the increasing demand for and the limited supply of materials. The construction industry consumes a great amount of global resources and generates a great amount of waste, and can contribute to the shift towards a circular economy by means of a more circular building stock. In theory, modular building can contribute to a circular building stock, by securing the future utility of the stock. Multi-configuration modular building allows for adjustment and relocation of the building and deconstruction and reuse of its piece parts. Based on a collective cases study of five suppliers of modular building, the degree to which modular building can contribute to a circular economy depend on the reason for, the interpretation of and the operationalisation of modular building.