Alternative aggregates, including recycled (concrete) aggregates as well as artificial aggregates (such as crushed stainless-steel slag), are being increasingly used in road construction in the context of a more circular economy (waste management and decreased extraction of primary materials), and to help lower the environmental impact of cement-based building materials (lower energy need for production and less CO2 emissions). As these materials are applied higher up in the road structure (surface and binder courses), stricter requirements are made to allow for higher loads and the stronger influence of the climate. Based on previous research, the Flemish standard specifications for road construction, for instance, allow incorporation of recycled concrete aggregates (RCA) in concrete pavements or linear elements in concrete, but only if certain stringent requirements are met and only up to certain percentages of substitution of the natural coarse aggregates. Currently, the focus shifted also to integration of the recycled sand fraction in new concrete due to scarcity of good quality natural construction sand in future. In addition, the use of alternative binders in road concrete compositions is also being investigated such as new ternary cements based on alternative supplementary cementitious materials (SCMs) or even geopolymers and alkali-activated materials. This paper presents an overview of laboratory research conducted in Belgium in recent years to characterize several types of alternative materials and concrete mixtures incorporating them, with a focus on practical execution as well as on the durability of pavement concrete. In addition, several concomitant pilot applications in Belgium are discussed in view of future perspectives for the use of alternative raw materials in a more sustainable and circular road construction.