Life cycle assessment (LCA) has been promoted as a robust quantitative tool, and a keystone in environmental decision making. While LCA was originally developed for products, the benefits of the life cycle approach may be extended to the more complex prospect of organisational assessment. Within this context, the UNEP/SETAC Life Cycle Initiative launched the flagship project “LCA of organisations” to further explore the capabilities and applicability of organisational life cycle assessment (O-LCA). This Guidance document is the main milestone of the project. It builds on key existing works and initiatives, like the Greenhouse Gas Protocol initiative, and especially strives to align with ISO/TS 14072, and with ISO 14040 and ISO 14044. They are referenced throughout the Guidance as a basis for the explanations and discussions.

O-LCA uses a life cycle perspective to compile and evaluate the inputs, outputs and potential environmental impacts of the activities associated with an organisation,and the provision of its product portfolio. This methodology is capable of serving multiple goals at the same time (e.g., identifying environmental hotspots throughout the value chain, tracking environmental performance over time, supporting strategic decisions, and informing corporate sustainability reporting). One goal that O-LCA cannot currently fulfill is externally communicating comparisons between different organisations. Comparative assertions are neither robust nor meaningful, mainly due to the lack of a consistent basis for comparison.

O-LCA is envisioned for organisations of all sizes, both public and private, in all sectors, and all over the world. The first tentative steps toward full O-LCA application are currently taking place, and the outcomes of these are already being used to improve organisations’ environmental performance. Broadening the base of implementation is the logical next step, requiring accessible, practical guidelines and guidance. Three different pathways describe how organizations with previous experience with environmental tools can use this as a basis to ‘think bigger’ and integrate an O-LCA approach. Additionally, specific recommendations for small, medium and large organisations provide practical ways forward. The specific directions given for several situations underscore that there is no ‘one-size-fits-all’ application of O-LCA. Eleven case studies, through on-the-ground experiences of ‘First Movers’, further illustrate the process and benefits of applying an environmental multi-impact assessment of organisations and their value chain.