The Wechsler Intelligence Scale for Children-Revised (WISC-R), one of the most commonly used tests of cognitive ability, is difficult to administer accurately. The purpose of this study was primarily to assess interrater agreement on the WISC-R Administration Observational Checklist (WAOC), a new observational instrument that can be used by an observer to evaluate all components of WISC-R administration. A secondary purpose of the study was to evaluate two WISC-R administrations of five students enrolled in a graduate course in psychoeducational assessment. Based on a total of 10 observations by two raters, Cohen's Kappa was calculated for 29 of the measures on the checklist. The values for 22 of the measures were significant (p greater than .05). The difference in mean scores for the first and second observations of the students did not quite reach statistical significance because of the small number of subjects and because of a ceiling effect for one student who scored highest on the first observation. However, after receiving feedback, students showed improvement on a number of the measures. WAOC enables the observer to pinpoint examiner errors and to give specific feedback regarding those errors. (Author/JAZ)