As modular weapon systems allow cost-effective upgrades of a vessel’s war-fighting capability, the degradation of the difficult-to-upgrade structure of the vessel may soon become one of the key drivers of vessel retirement and lifecycle maintenance costing. Existing structural design approaches are reviewed, along with recent developments in this field. It is argued that recent research has produced a number of ad hoc metrics for structural design, such as producability; however, to truly address the needs of future ship design teams it is necessary to integrate several such metrics in a systems-engineering view to evaluate how the structural system contributes to the overall capabilities and costs of a proposed vessel. Potential architectures for this approach are discussed, along with key shortcomings. A comparative example is given for structural fatigue of a strength deck under global bending loading, comparing the traditional design approach with a systems-oriented view.