Problem statement – As a result of the increasing world population, use of raw materials and energy, scarcity of the raw materials and the pressure on the environment, a transition to the concept of a circular economy has become more urgent. Since the Dutch government has the ambition to be fully circular in 2050, the concept of a circular economy is more and more linked to area development in the Netherlands. As a result, existing inner-city production areas are, partly because of urbanization, being transformed through a circular design approach into residential and commercial areas. However, due to these transformations, production processes disappear from areas, which in fact makes the areas less circular because the circular functioning in the areas is no longer included. Hence it can be questioned in what extent contemporary circular area developments are actually circular, or whether these circular area developments only consist of a circularly designed area that does not take into account the circular functioning of the area. Objective – The main objective of this research is to understand how circular functioning can be taken into account in the development of circular areas. Based on the understanding of how the circular functioning of an area is or is not taken into consideration during circular area development, recommendations will be drawn up. The research question that is answered: ‘’Which recommendations can contribute to an area development with regard to the circular functioning of an area?’’. Methods – The research process is divided in three parts. First of all, a literature review has been carried out to collect information in order to gain an understanding and insights about circular area development. Secondly, a case study and several interviews are conducted in order to gain insights of what criteria the recommendations should suffice to with the aim of improving the circular functioning of an area during a circular area development. Thirdly, an expert panel is held to validate draft recommendations to ultimately formulate final conclusions and recommendations. Results – The results of this research show that circular area development consists of a circularly designed environment and a circularly functioning environment, in which the use of resources and energy is minimized by closing, slowing down and narrowing cycles. In addition, a circular area consists of as much local production and transactions as possible, creating opportunities for the highest possible reuse of products, materials and resources. Further findings claim that area development can significantly change an area's program. As a consequence of an increasing program, material consumption and waste generation increase within an area. It can therefore be argued that, with regard to the circular functioning of an area undergoing an area development, more processing of materials and waste should take place as locally as possible. Conclusion – Several recommendations have been identified in this study that can be divided into three categories. First, overarching recommendations focus on (1) the specific formulation of guidelines for achieving sustainable and circular objectives and (2) stimulating innovations during area developments. Second, the focus should be on creating both a circularly designed area and a circularly functioning area during area development. This category consists primarily of rethinking the development plans, by analysing the current situation in the area and assessing how the current built environment, infrastructure and established activities can contribute to a circular economy. Subsequently, the following five aspects can be applied: (1) circular criteria for land issues and tenders, (2) design and build according to circular principles, (3) new forms of financial value assessment, (4) introducing flexibility in the existing zoning plan, and (5) stimulating local partnerships to close cycles. The third category, monitor, evaluate and improve, serves to assess whether the sustainable and circular objectives of an area development are achieved and, if possible, to make adjustments to improve the sustainability and circularity of an area. This category consists of the following six components to monitor, analyse and improve: (1) incoming and outgoing flows in an area, (2) existing and future raw materials in an area, (3) energy consumption of an area, (4) climate adaptation of an area, (5) health and well-being of residents in an area, and (6) local economy. Discussion – COVID-19 broke out during the research process. On the one hand, this created obstacles for the research: respondents were often not available for interviews. Nevertheless, all questions previously drafted in the protocols have been answered. On the other hand, the coronavirus outbreak has shown that the circular economy principle is more topical than ever, in which port cities in particular should focus more on less volatile manufacturing industries rather than international processes. As a result, countries will be less dependent on international processes and besides, the total number of international transactions will reduce. This given is in line with the principle of a circular economy. Moreover, the focus on less volatile manufacturing industries of port cities will eventually create new job opportunities for local residents. In other words, bringing (re)consumption and (re)production back or closer to port cities not only contributes to the ecological aspect, but also to the local economy.