E-waste, price volatility of resources and the constant increase of the middle class world population expecting the same ‘high quality’ life standards have (amongst other) made some companies consider their options. In the reports of the Ellen MacArthur Foundation, one aspect of the circular economy model aims at decoupling sales revenues from material input using a restorative industrial economy by intention and design. In contrast to the current model, products are designed for maintenance, reuse, refurbishment, remanufactured and/or recycling. Special care is put in thinking how to reuse the totality of the materials and reclaim the embedded value in end-of-life (EoL) products. The current linear consumption situation of the sector was analysed in order to identify guidelines, challenges and opportunities to the implementation of circular economy principles. Since no design guidelines have been published for the development of circular products, various guidelines were gathered from literature on inter alia design for disassembly, design for maintenance, design for refurbishment, design for remanufacture and design for recycling. These were combined and organised in five categories: Product Structure, Components, Materials, Joints and Accessories. Multiple threats to the application of circular thinking exist with respect to society & customers, design, manufacturing, EoL and economics. For example, the complexity of the map of stakeholders, the complexity of the composition of current mobile phones, the lack of knowledge on the topic throughout the value chain, customer behaviour and confidentiality issues might stand in the way of circularity. Various opportunities for circular systems and products can be seized. Public procurement and B2B can be seen as interesting targets for the introduction of circular devices and business models (as compared to consumer customers). By offering a lease-like programme, users can have access to personalised performances and upgrade products to meet these performance requirements during their contract period with a mobile network operator. The operator could thus remain in control of the embedded resources. Collaboration cross cycles and sectors will be essential for the success of this model. The drafted guidelines, challenges and opportunities were translated into concrete characteristics for a desired circular future product and system in the mobile telecommunication industry for an advanced scenario (technically possible within ten years). The design named BlackbOx has standardised 3D printed components, durable and self-healing materials, and is completely recycled and recyclable. Active disassembly techniques have been integrated to ensure an efficient, effective and profitable treatment circular process. A roadmap describing the steps from the current situation to this desired situation was made. Both the system and the products are further detailed for each milestone. The first milestone focusses on the low hanging fruits. The second and third ones are concentrating on making the most important components circular. In an advanced scenario (fourth milestone), all components are becoming circular. Finally in a truly circular economy (fifth milestone), the whole system and product are designed to create no waste. A second product was developed for the first milestone so as to embody the previously formulated characteristics and assess the drafted guidelines. It could be in use by employees in the public and private sector within a period of two years. The aim of this product development was to decrease costs on maintenance and refurbishment operations and lower the barriers for customers to hand in their old devices. The ratio between the labour needed to retrieve components and the value of the involved components and materials had to be improved. The designed mobile phone has a durable and minimalistic design suitable for the users. The product is also built from the inside out. The components to be prioritised are standardised and modular using joints utilised in other commercially available products. As a result, these can be more easily disassembled therefore more simply repaired, upgraded, refurbished, remanufactured and recycled. The set of drafted guidelines were evaluated during the two product developments and fine tuned to be used by other industrial designers. Key characteristics of a circular mobile device can be summarised to: built to last, easy to disassemble, modular parts, standardised components and joints, upgradeable components, materials cycle through the various CE circles (‘waste’ is used as input), uncontaminated material flows, and finally, tight CE circles are preferred thoughout the life of the product.