ISO 21349:2023

Overview - ISO 21349:2023 (Space systems - Project reviews)

ISO 21349:2023 defines process requirements for project reviews in space systems. The standard specifies a set of required functions, their inputs, outputs, mechanisms and controlling conditions, and clarifies the responsibilities of a review board and guidance on review board composition. ISO 21349:2023 applies to status reviews at any project level and to major milestone reviews at top-level projects. It is intended for use by independent developers, as the basis of enterprise processes, or as part of supplier–customer agreements to implement formal review requirements in space programmes.

Key topics and technical requirements

• Structured review process: A process model and function hierarchy are provided; the standard requires implementation of twelve third‑level review functions (see Clause 5) to ensure consistent review conduct.
• Inputs and outputs: Requirements and recommendations for evidence, project data files, milestone criteria and expected outputs of reviews.
• Roles and responsibilities: Defines roles such as review board, review board chairperson, review board members, project review team, project expert, independent expert, and project decision authority.
• Preconditions and controls: General and specific preconditions for initiating a review, plus mechanisms to coordinate concurrent functions and control interruptions or resource conflicts.
• Review lifecycle activities: Initiate review, prepare and publish evidence, assess project status (evaluate evidence quality and achievements), conclude review (recommendations, action plans, decisions, closure).
• Guidance on review types: Descriptions of common review kinds useful for assuring success across project phases and transitions.

Practical applications and who uses ISO 21349

• Space programme and project managers use ISO 21349 to standardize milestone reviews and acceptance criteria across project phases.
• Systems engineers and configuration managers leverage the standard to prepare and evaluate project data files and evidence.
• Quality assurance, risk managers, and review board chairs use it to structure independent, objective evaluations and to assign action plans and decisions.
• Contractors and customers use ISO 21349 as a contractual baseline for formal reviews, improving communication, reducing planning costs, and managing phase‑transition risks in complex space projects.

Benefits

• Ensures consistent, transparent review practices across organizations
• Clarifies responsibilities for objective evaluation and decision-making
• Supports risk-informed transitions between project phases and milestones
• Facilitates supplier–customer alignment on review expectations

Related standards

• ISO 14300-1 and ISO 14300-2 (project lifecycle milestones and review requirements)
• ISO 15865 (for related space system requirements)
• ISO 17666 (risk management) and ISO 10795 (vocabulary) - normative references in ISO 21349

ISO 21349:2023 (second edition) updates terminology and normative references from the 2007 edition and is intended to be used alongside other space systems and operations standards that require formal reviews.