The Guidelines for Social Life Cycle Assessment (S-LCA) of Products provide a roadmap and a body of knowledge to help stakeholders in the assessment of social and socio-economic impacts of products’ life cycles, their related value chains and organizations. Awareness about value chain social issues such as child labor used for harvesting cotton, unpaid wages of factory workers and safety issues when using a product, raises the question of what the extent of product and organization social impacts are and how they can be improved. To answer this question, the S-LCA Guidelines present a methodology to assess the social impact of products using a life cycle perspective. This methodology builds on the more commonly known Life Cycle Assessment (LCA), which focuses on environmental impacts. A key and unique feature of S-LCA, within the landscape of social assessment methodologies, is that a life cycle perspective is used to assess the social impacts of a product or organization. This means looking not only at the factory or process that produces the product, e.g. flour milling, but also at the social impacts related to all the associated processes, both upstream and downstream, e.g. grain production, transport and final distribution of the flour. In the past decade since the original S-LCA Guidelines were published, S-LCA has gained in maturity and established itself as a standalone methodology. These 2020 Guidelines provide additional information and consensus-based guidance for each step of the S-LCA, explaining the strengths and challenges of different approaches to address a varied set of questions related to the social sustainability of products and organizations. For instance, to support measuring and assessing progress towards the UN Sustainable Development Goals (SDG). The expanded framework builds on the previous edition to cover new methodological and practical developments such as social organizational LCA (SO-LCA) as well as the refinements and additions of social impact subcategories that have emerged in the literature and that are now integrated in the guidance.