Redefining Sustainability and Sustainable Development: From Economic Foundations to the Proposal and Implementation of a New Conceptual Framework

Abstract

Sustainability and sustainable development remain vague concepts in economic analysis, complicating policy application and theoretical progress. In this paper, we address these conceptual gaps by introducing the Sustainable Development System (SDS), a dynamic framework that distinguishes sustainability as normative guidance from sustainable development as context-specific, emergent processes shaped by adaptive feedback across economic, social, and environmental systems. The SDS synthesizes insights from classical, neoclassical, ecological, institutional, and behavioral economics through a three-layer variable architecture: standard development determinants, context-specific factors, and strategic leverage points. Applying the SDS to Morocco and Senegal for the period 2025–2045, we demonstrate how different institutional capacities and adaptive governance mechanisms produce divergent sustainability trajectories under the exogenous effects of globalization. Our internally validated simulations confirm the framework's theoretical coherence, advancing sustainability economics toward practical, adaptive modeling tools that support resilient development strategies.