This article discusses quantitative metallography models for life assessment, component sampling techniques, and remaining life assessment using postexposure testing. The recovery creep model for 1Cr-1/2Mo base material uses the interparticle spacing measured on carbon extraction replicas to calculate the strain-time curve. The constrained cavity growth metallographic model for the HAZ material measures the number fraction of grain boundaries undergoing cavitation by light optical microscopy and predicts the fraction of rupture life consumed by prior service. The widely used Neubauer qualitative level was shown to correlate with the life fraction consumed. The remaining life prediction techniques for elevated temperature headers include isostress direct temperature extrapolation, the life fraction rule, and strain assessment techniques.