Every year, large volumes of imagery are collected for the sole purpose of evaluating Automatic Target Recognition (ATR) algorithms. However, this data cannot be used without adequate truthing information for each image. Truthing information typically consists of the types and locations of the targets present in the imagery. Specifying this information for a large number of images is tedious, time consuming, and error prone. In this paper, we present a complete truthing system we call the Scoring, Truthing, And Registration Toolkit (START). The first component is registration, which involves aligning heterogeneous and homogenous sensor images of the same scene to a common reference frame. Once that reference frame has been determined, the second component, truthing, is used to specify target identity, position, orientation, and other scene characteristics. The final component, scoring, is used to assess the performance of a given algorithm as compared to the specified truth. The scoring module allows statistical comparisons to assess algorithm sensitivity to specific operating conditions (e.g., sensitive to object occlusion).