The main projects within this area involve circular economy initiatives, and the analysis, planning, design, implementation, and ex‑ante and ex‑post evaluation of environmental economic policies, including a threefold economic, environmental, and legal perspective. To do this, ENT draws on principles and methods from ecological economics, environmental economics, and public economics. One of the main areas of expertise is environmental taxation and, more broadly, economic instruments of environmental policy, in which ENT has worked from the local level (for example, developing projects to incorporate environmental criteria into fiscal ordinances or waste charges) to the regional and national levels (e.g., drafting legislative proposals for new environmental taxes) and the international sphere.

ENT has experience in material flow projects and in the use of applied economic methods, such as statistics and quantitative techniques, econometric modelling, economic impact assessment, input–output analysis (monetary, physical, and environmental), computable general equilibrium modelling, environmental and intangible valuation, ecosystem services valuation, public and private project evaluation, and cost–benefit and cost‑effectiveness analysis, among others.

In recent years, ENT has also specialized in the field of responsible public procurement, which includes green public procurement and socially responsible public procurement. In this regard, it provides support for the integration of environmental, social, and ethical clauses into specific contracts and assists public administrations in systematizing their responsible purchasing and contracting practices.