Additive Manufacturing (AM) practices are continuously improving, going far beyond the initial (and still relevant) applications of rapid-prototyping, progressing toward the development of intricate, customized, technology-driven high-value components in the aerospace, automotive, and biomedical industries. This section presents an in-depth account of the Powder Bed Fusion (PBF), Material Jetting (MJ), and Directed Energy Deposition (DED) practices with an analysis of their respective classifications, mechanisms, and industrial applications. Attention is given to the engineering of the feedstock, and the respective powders, powdered metals, polymers, ceramics, rubber, and composite materials, and the innovative, engineered, and eco-friendly materials. Further, feedstock-related AM challenges of defect, distortion and distortion, and roughness (texture) are integrated with quality assurance in the form of in-situ monitoring, technique (quanta) testing, and the regulating and controlling structures (standards) of the ASTM F2924 and ISO 52900 frameworks. Repeatability and certification rested in the focus of the AM frameworks cited. The emphasis is on sustainable process control. This is the future of intelligent, industrial-grade additive manufacturing, the sustainable and modeled process control.