NDE decisions differ from most other engineering decisions in that the NDE response or responses used in making a decision with regard to the serviceability of a part are often only weakly correlated with the serviceability of the part. The impact of of this weak correlation or inspection uncertainty on inspection errors and the effectiveness of the inspection is discussed. A quantitative methodology for selecting the optimum NDI accept/reject decision thresholds in the face of the inspection uncertainty is outlined. Also discussed briefly is how inspection uncertainty analysis can be used to estimate the inspection reliability from field or production inspection data without the use of a flawed specimen program