Sufficiency in principle and practice: An operational definition and typology

Sufficiency is emerging as a necessary concept as safe and just Earth system boundaries are increasingly transgressed, yet its definition and operationalisation remain fragmented. In this paper, we provide an operational definition for the concept, defining sufficiency as a state of enoughness that avoids both deficiency and excess in relation to fair social and ecological limits. Then, we develop a typology for the classification and analysis of practical sufficiency measures through a theory-informed content analysis of 1,101 proposed measures drawn from three diverse datasets. The resulting typology identifies five distinct types of sufficiency measures: quantitative, qualitative, use, sharing, and steering. To demonstrate the applicability of our typology, we test it against 33 policies presented in the “Sufficiency Manifesto” for the European Union, classifying policies based on the sufficiency measure type and whether they targeted the household, private, or public sector. Our analysis shows that all five types of sufficiency measures were present, though unevenly, with sharing measures least represented. This demonstrates how the typology can reveal patterns or gaps in current approaches and highlight opportunities for more comprehensive strategies. By developing an operational definition of sufficiency, clarifying its implications in both principle and practice, and offering a typological tool for analysing sufficiency measures across sectors and scales, this study advances the conceptual foundations and operationalisation of sufficiency, providing an empirically grounded framework for its systematic application.