The advent of new technologies and the introduction of additive manufacturing ushered in the era of Industry 4.0 years ago. For organisations to remain competitive, becoming sustainable is no longer an option, but a requirement, as sustainability has become a critical success factor. Controlling the emission of harmful and polluting gases, using energy and raw materials efficiently within the company and recycling waste products are all viable solutions for achieving sustainability.[82] This thesis aims to analyse the positive environmental and economic aspects of additive manufacturing applications, particularly WAAM (Wire Arc Additive Manufacturing), through a systematic literature review. The concept of remanufacturing is closely linked to the idea of circular economy, which aims to minimize waste and promote the reuse of materials by repairing them and extending their useful life, thus delaying their disposal.