Now we have gained a first understanding of the imaginary that is guiding circular economy policy development, we focus on a particular site that we argue is central in the negotiation and imagination of circularity and for questions about circular economy policies: the indicators that are being developed for measuring progress towards a circular economy. Drawing on a rich literature from the field of science and technology studies on the role of quantification in governance and the politics of indicators this chapter explores how circularity becomes both a measurable and governable entity and how particular circularities (and realities) are enacted at the expense of others. The purpose of the critical analysis presented in this chapter is also, however, to go beyond deconstruction and direct attention to potential implications of measuring circularity in certain ways. This chapter thus presents a reading of indicator development inspired by STS literature that highlights the productivity of measurement in governance practices. As Esther Turnhout so poignantly stated: “only what is counted counts”.