Damage denotes the aspects of chronic disease that do not reverse with therapy. This concept is particularly important for the primary systemic vasculitides, since the careful differentiation between activity and damage may help avoid unnecessary exposure to cytotoxic medications. Damage significantly influences both longterm prognosis and quality of life. Because the primary systemic vasculitides have diverse manifestations, the use of a damage assessment instrument is crucial to ensure reproducibility. The Vasculitis Damage Index (VDI) is the only validated measure for damage assessment in vasculitis. Use of the VDI in recent clinical trials has shown that it may not adequately determine the full spectrum of damage experienced by patients with vasculitis of small- and medium-size vessels. We propose reexamining the way in which damage is assessed, focusing on vasculitides of small- and medium-size vessels, and outline an initiative to create a substantially revised and improved damage assessment instrument using data-driven approaches. This initiative is part of a larger international effort to create a unified approach to disease assessment for the primary systemic vasculitides.