For Texas's Career Ladder System of rewarding good teachers, teachers' performance evaluations from 1981 to 1984 were used to rank teachers in the Austin Independent School District. Significant biases were noted between raters, between years, and between elementary and secondary teacher ratings. To adjust for these biases, each teacher's raw score average was converted to a z-score, and adjusted for the factors associated with bias. The final z-score was used to determine selection for the Career Ladder; quota systems were not used. A small correlation was noted between teachers' z-scores and elementary school students' reading and mathematics achievement on the Iowa Tests of Basic Skills. Teachers' raw scores were less able to predict student achievement. However, z-scores were not well received. This technique was eventually abandoned due to: (1) dissatisfaction and distrust; (2) changes in legislation and confused communication; (3) the non-selection of some key teachers; (4) differing goals of the teachers' associations; and (5) the provision of additional funding for a greater number of career ladder teachers, which made z-scores unnecessary. (GDC)