This study was designed to investigate the empirical consequences of building tests for which the size of the difference in average scores between Black and White examinees is made to be as large and as small as possible within certain constraints. Test forms for two item types were developed that maximized or minimized the differences in average scores between Black and White examinees. The test forms were then administered to a random sample of examinees along with conventionally constructed control forms. The results suggest that impact manipulation is possible while maintaining content specifications and average difficulty level. However, the distribution of item difficulties was altered as were the reliability of the experimental sections and the relationships of these sections to other parts of the test. (Author/TJH)