In the last decade, sintering technologies have developed rapidly, progressing from conventional heat treatments towards advanced and hybrid approaches capable of meeting the increasing demands placed on new materials. This chapter presents a comprehensive review of the main advanced sintering techniques, including spark plasma sintering (SPS), hot isostatic pressing (HIP), microwave sintering, and other field-assisted sintering (FAST) methods. In this way, fundamental process mechanisms, critical processing parameters, and comparative advantages over conventional sintering are presented, with a focus on achieving rapid densification, refined microstructures, and improved functional performance in ceramic, metallic, and composite materials. In the second part, we focus on sintering in the context of additive manufacturing as a hybrid technology, addressing the main classes of additive processes, such as direct energy deposition, material extrusion, material jetting, sheet lamination, vat polymerization, and powder bed technologies. Attention is paid to binder jetting processes, subsequent sintering, selective laser sintering, and post-processing heat treatments, which play a key role in improving densification, mechanical properties, and microstructural homogeneity. Hybrid manufacturing routes are also discussed as promising strategies that integrate additive processes with advanced sintering, allowing the overcoming of limitations related to geometric complexity, material compatibility, and performance optimization. By correlating advances in sintering science with innovations in additive manufacturing, the chapter provides an integrated perspective on the role of emerging methods in the development of the next generation of functional materials for biomedical, structural, and energy applications.