directory of policy at HEFCE, came to the conclusion that the research assessment needed to become "much more robust and rigorous." This led to the institution of the Research Assessment Exercise in 1992. The results of the 1992 results were nevertheless challenged in Court by the Institute of Dental Surgery and the judge warned that the system had to become more transparent. The assessment panels in the subsequent exercises had to be much more explicit about the criteria for evaluation and the working methods. In 1996, all volume-based evaluation was removed to account for the criticism that volume rather than quality was rewarded. The 1992 exercise also stipulated that the staff submitted for assessment had to be in post by a specific date (the "census date") in order to counter the criticisms that the staff that had moved on were still counted in the assessment. This led to the phenomenon of "poaching" of highly qualified staff by other universities ahead of the census date. In the 2001 exercise, the credit for the staff that moved institutions in the middle of the cycle could be shared between the two institutions. In the 2008 exercise, this was abolished. The assessment of 2008 also brought in a major change. Instead of a single grade for an entire subject area ("unit of assessment"), a grade was assigned to each research output. This was done to counter the criticism that large departments were able to hide a "very long tail" of lesser work and still get high ratings and, conversely, excellent staff in low-graded departments were unable to receive adequate funding. Thus the single grades for units of assessment were replaced by "quality profiles," which indicated the proportion of each department's research against each quality category. Scale 2008 The 2008 RAE used a four-point quality scale, and returned a profile, rather than a single aggregate quality score, for each unit. The quality levels—based on assessment of research outputs, research environment and indicators of esteem—are defined as: Each unit of assessment was given a quality profile – a five-column histogram – indicating the proportion of the research that meets each of four quality levels or is unclassified. Earlier Assessments In 1992, 1996 and 2001, the following descriptions were used for each of the ratings. These ratings have been applied to "units of assessment", such as French or Chemistry, which often broadly equate to university departments. Various