The roadside vegetation artificially forms a green ecosystem on the basis of a grey system – transporting infrastructure with geotechnical soils. Such a “green-on-grey” system, namely roadside ecosystem, can provide a list of ecosystem services (ESs). Both research and practice on the multifunctionality of roadside ecosystem are highly lacking. The Opus VI project aims at optimizing our vegetation management (via mobilizing three levers at different scales: species selection and mixture at intra-layout unit scale and layout arrangement at the whole road scale) for an ecologically multifunctional the roadside ecosystems in a sustainable manner.