Achieving sustainable development necessitates a balanced, rigorous, and simultaneous evaluation of its three fundamental dimensions: economic, environmental, and social. However, among these, the social dimension has consistently faced greater theoretical ambiguity and operational challenges. Historically, development-oriented projects have prioritized economic and environmental metrics, often relegating social factors to a secondary status. This misconception stems from an anthropocentric view that places humans in dominance over nature, whereas true sustainability recognizes human dependence on resilient, long-term livable communities. Social Sustainability Assessment (SSA) and Social Life Cycle Assessment (S-LCA) have emerged as critical tools to address this gap. Yet, despite guidelines from UNEP/SETAC, these frameworks often operate in isolation, leading to fragmented evaluations, methodological inconsistencies, and limited practical applicability in real-world settings.

A critical review of the literature reveals a significant methodological gap: the absence of a coherent, unified theoretical framework that effectively integrates SSA with life cycle methods. S-LCA, while robust in its process-oriented, phase-by-phase structure, often suffers from a lack of consensus on standardized indicators and struggles to capture macro-level policy impacts. Conversely, SSA provides strong, indicator-based, holistic evaluations of social sustainability but lacks the systematic, temporal tracking of impacts across a project’s entire life cycle. Consequently, social assessment tools have not been effectively embedded into various stages of project life cycles, reducing transparency, fairness, and efficiency in decision-making.

To bridge this critical gap, this study aims to develop and propose an innovative, comprehensive, and integrated model termed the Sustainable Social Life Cycle Assessment (SS-LCA). This model strategically merges the structured, indicator-based strengths of SSA with the process-oriented, life-cycle perspective of S-LCA, creating a unified framework for assessing the social sustainability of development projects.

This research employs a qualitative, exploratory, and applied approach. Data collection and analysis were conducted in two main stages. First, a systematic literature review was performed following PRISMA guidelines and the PICo framework, searching reputable databases (Scopus, Web of Science, ScienceDirect, SpringerLink, and Google Scholar) for studies published between 2000 and 2024. Second, the extracted data underwent Qualitative Content Analysis (QCA) and meta-synthesis, utilizing a modified version of Jabareen’s (2009) conceptual framework development method. This modified process involved mapping interdisciplinary data sources, reviewing and classifying content, conducting conceptual analysis of S-LCA and SSA, extracting common features, establishing the necessity of integration, and ultimately synthesizing the novel integrated framework.

The resulting SS-LCA model is structured as a cohesive, seven-phase operational framework designed to guide practitioners and researchers:



Goal Definition and Context Analysis: Establishing the assessment's purpose, identifying the project context, and mapping all relevant stakeholders (local communities, workers, policymakers, NGOs).

Scope Definition: Delineating system boundaries, identifying life cycle segments, and determining the depth of the social assessment.

Social Life Cycle Inventory (S-LCI): Collecting and prioritizing social data using general information, site-specific data, and the Social Hotspots Database (SHDB), supplemented by field methods like interviews or surveys.

Assessment of Social Life Cycle Impacts: Transforming inventory data into impact analyses using descriptive and quantitative models (Type 2 S-LCA), categorizing indicators by stakeholder groups.

Analysis of Social Impact: Evaluating the significance, likelihood, and intensity of identified impacts, considering stakeholder responses and distinguishing between short-term and long-term consequences.

Examination of Dependent Social Impacts: Analyzing synergies, conflicts, and major consequences of project actions to propose targeted mitigation strategies that enhance positive outcomes and reduce negative ones.

Interpretation of Results: Synthesizing findings, documenting research limitations, outlining stakeholder involvement, and providing actionable recommendations for policy and project management.

The findings indicate that the SS-LCA framework successfully overcomes the isolated limitations of its predecessor models. By linking micro-level project assessments with macro-level strategic policy goals, the model ensures a comprehensive view of social impacts from "cradle to grave." It effectively balances quantitative measurements with qualitative valuations of justice, equity, and participation. Furthermore, the model significantly enhances multi-criteria, responsible decision-making and fosters deeper, more ethical stakeholder engagement throughout the project lifecycle. Practical applications, such as in integrated natural resource management projects (e.g., the MENARID project), demonstrate that addressing social components like trust, participation, and capacity building is a strategic necessity, not a secondary choice, for long-term project sustainability.

The SS-LCA model represents a significant theoretical and practical advancement in the field of social sustainability. It provides a robust, generalizable, and transparent tool for evaluating development projects, ultimately facilitating intergenerational justice and sustainable community resilience. While limitations such as data accessibility and methodological complexity exist, the framework lays a solid foundation for future empirical testing, local adaptation, and the institutionalization of integrated social assessments in global sustainable development policies.