Circular, data-driven healthcare is increasingly being considered as an effective model to provide efficient, cost-effective and sustainable healthcare services in the future. Central to this model is the service-dominant "building-block"-type provision of care services to patients, paired with the collaboration of healthcare providers through a common infrastructure. This combination enables the forming of a decentralized, holistic care cycle. Sharing of patient medical information is pivotal towards reaching this goal; however, preserving medical record integrity and privacy, while at the same time allowing provider interoperability are often conflicting requirements. Blockchains and Smart Contracts can provide the underlying technology to support the decentralized care cycle by addressing patient privacy and medical record integrity, while simultaneously offering efficient interoperability between providers. To demonstrate how this could be achieved, a conceptual medical record access and sharing mechanism is presented which is suitable for a system operating within a regulated healthcare jurisdiction.

Implementing a circular economy business model which is profitable for businesses operating physical assets, while at the same time does not conflict with strategic goals of environmental policies can be a complex and risky undertaking for a single entity, especially if the asset operator is a small-to-medium enterprise (SMEs). To mitigate this, a collaborative circular economy business model is proposed, where the circular economy cycle is materialized by assets transitioning between asset operators on a demanddriven approach. Demand itself is partially based on the asset's state, which is described by its circular properties (location, condition, availability). The asset state and its transition between operators can be monitored by auditors and governmental regulators to ensure asset integrity and compliance with environmental targets. This common view of asset state between all parties can be enabled by blockchains and smart contracts, which can provide the underlying technology to share data with integrity, while simultaneously offering more efficient interoperability between participants. To demonstrate how this could be achieved, a conceptual asset record access and sharing mechanism is presented which is suitable for regulated environmental jurisdictions.

The increase in the world's population has led to a massive rise in human consumption of the planet's natural resources, well beyond their replacement rate. Traditional recycling concepts and methods are not enough to counter such effects. In this context, a circular economy (CE), that is, a restorative and regenerative by-design economy, can reform today's "take-make-dispose" economic model. On the other hand, the Internet of Things (IoT) continues to gradually transform our everyday lives, allowing for the introduction of novel types of services while enhancing legacy ones. Taking this as our motivation, in this article we analyze the CE/IoT interplay, indicating innovative ways in which this interaction can drastically affect products and services, their underlying business models, and the associated ecosystems. Moreover, we present an IoT architecture that enables smart object integration into the IoT ecosystem. The presented architecture integrates circularityenabling features by maximizing the exploitation of assets toward a new type of IoT ecosystem that is circular by design (CbD). Finally, we provide a proof-of-concept implementation and an application study of the proposed architecture and results regarding the applicability of the proposed approach for the telecommunications (telecom) sector.