A Requirements-Based Extension of Earned Value Management for Engineering Project Control

Engineering projects deliver capability by closing requirements, but progress is often inferred from budget recognition rather than verified requirements closure. In systems-intensive settings, this practice can misstate technical maturity because expenditure may increase during investigation, rework, integration, or approved baseline change without a corresponding increase in delivered capability. Standard Earned Value Management (EVM) integrates scope, schedule, and cost performance, but its earned-credit logic does not show whether requirements-level capability has been closed. This paper develops Requirements-Based Earned Value Management (RB-EVM), a conceptual extension that preserves conventional EVM reporting while adding an earned stream based on time-phased, auditable requirements closure. The framework reformulates earned credit around requirements lifecycle closure, derives normalized and budget-scaled requirements-based measures, and introduces the Requirements Performance Index as a schedule-like indicator of whether audited technical closure is keeping pace with the approved requirements baseline. It also defines a divergence diagnostic that makes disagreement between budget-recognized progress and requirements-based progress explicit and identifies the governance conditions needed for valid interpretation. RB-EVM complements rather than replaces standard EVM: conventional indicators retain their roles in financial execution and cost-schedule governance, while requirements-based measures make technical closure visible and comparable with those signals. Applicability depends on a traceable requirements register, auditable closure evidence, a time-phased requirements baseline, stable weighting rules, and disciplined change control.