This Technical Specification provides additional specifications to ISO 14040:2006 and ISO 14044:2006. It provides requirements and guidelines for conducting a critical review of any type of LCA study and the competencies required for the review. This Technical Specification provides: — details of a critical review process, including clarification with regard to ISO 14044:2006; — guidelines to deliver the required critical review process, linked to the goal of the life cycle assessment (LCA) and its intended use; — content and deliverables of the critical review process; — guidelines to improve the consistency, transparency, efficiency and credibility of the critical review process; — the required competencies for the reviewer(s) (internal, external and panel member); — the required competencies to be represented by the panel as a whole. This Technical Specification does not cover the applications of LCA (as illustrated in ISO 14040:2006, Figure 1).