In the last three decades, water shortages have become more common and have left an increasing and significant mark on the world economy. The lack of water in arid and semi-arid regions, along with the interest in water security in areas where the demand for water exceeds its availability, has caused water reuse to be considered as an alternative source in these areas and has prompted the authorities to change from the usual linear, take–make–use management approach to the circular management of resource preservation. This new approach to sustainable management, using the management of reduction, reuse, recycling, and recovery, is called the circular economy (CE). However, although the potential for the reuse of treated wastewater is still insipient, CE in the water sector has gained a lot of attention lately. The aim of this paper is to systematically examine existing research published in the last five years on CE implementation in the water and wastewater sector. A sample of 64 articles was found through interactive keyword selection. Using the dynamic reading technique, data were extracted, and articles were classified according to five research motivations, which include, political, economic, legal, institutional, technical, and environmental. Most publications were from institutions in Europe, followed by North America and Asia. A similar trend was observed in terms of the distribution by authors, countries, and regions.