For product designers, the world has traditionally been one of resource abundance. Introducing them to a resource-constrained world thus requires new design strategies. This chapter explores how embedding circular economy principles into design practice and education could help product designers take critical material problems into account. We introduce four product design strategies that address materials criticality: (1) avoiding and (2) minimizing the use of critical materials, (3) designing products for prolonged use and reuse, and (4) designing products for recycling. The 'circular' strategies (3) and (4) are elaborated, as these sit most firmly within the remit of product design. This leads to a typology of circular product design that redefines product and material lifetime in terms of obsolescence, and introduces a range of approaches to resist, postpone or reverse product and material obsolescence. The typology establishes the basis for the field of circular product design, bringing together design approaches that were until this date unconnected and paving the way for the development of detailed design methods.