This Special Issue was launched in connection with the joint XIII National Congress of AICIng (the Italian Association of Chemistry for Engineering) and the II National Congress of the Division of Chemistry for the Technologies of the Italian Chemical Society, held at the Politecnico di Milano (Italy) from 25 to 28 June 2023. The aim of the Congress was to present and discuss recent advances in fundamental and applied chemistry in the fields of new or improved technologies, comprising compounds, materials, or processes. In this Special Issue, we pointed out that chemistry provides a molecular-level tool, allowing for significant advances in current and novel technologies in a wide range of fields. In this Special Issue, we collected selected relevant examples of the chemical foundations of the technologies that produced the new, scientific, and technologically innovative results obtained in Italy and elsewhere, in which various methodologies and approaches were used to design new products, materials, or processes in a wide range of fields.