ABSTRACT.- Sustainable intensification (SI) has become a central issue in both academic and political-institutional debates. Questions mostly center on the term's conceptual scope. In this article, we outline an operational definition of SI based on (1) a more explicit characterization of the intensification process that describes the intensity/magnitude of the management interventions generating stress or disturbances in the system, (2) a description of the relative change in sustainability based on quantifying ecosystem services supply changes among alternative uses, and 3) the definition of "impact functions" of a given management intervention as the relationships between the level of supply of given ES (or a "bundle" of ES) and an indicator of the intensification process. © 2022 Springer Nature, AESS.