A very important reading task in professional life is “reading to assess”: professionals have to form judgements on the basis of documents. Hitherto, the research into reading-to-assess tasks has been very fragmentary and incoherent. To develop a comprehensive theory of reading to assess, this article presents descriptions of 20 reading-to-assess processes of Dutch parliamentarians reading policy documents. All subjects read their document while thinking aloud. The thinking-aloud comments and the observations of their behavior resulted in different styles for the three aspects that constitute reading to assess: information selection, information processing and reading goals. These styles make it possible to characterize individual reading-to-assess processes, and to distinguish reading-to-assess from other reading tasks in the realization qualities of the task.