To test the applicability of multidimensional ratings of writing effectiveness that are amenable to normal classroom usage, all grade 7 students (N=139) from one suburban school (Sydney, Australia) wrote a brief essay. Master and student teachers evaluated all the essays according to overall effectiveness of written expression and according to holistic ratings of specific components (mechanics, sentence structure, organization, word usage, content/ideas, and style). Ratings of writing effectiveness by master teachers and by student teachers were substantially correlated with each other and with an external validity criterion. Correlations were particularly high for the sum of ratings of specific components, but were nearly as high for overall, global ratings. The single-rater reliability (r=0.7), the average of correlations between each pair of raters, was higher than expected from previous research. The average of single-rater reliabilities for specific components (r=0.6) was also high. However, the predicted ability of teachers to discriminate among the multiple components, except perhaps the mechanics facet, was not supported in a variety of multitrait-multimethod analyses. The student teacher ratings were nearly as reliable and as valid as master teacher ratings, and student teachers were prehaps better able to differentiate among different components of writing effectiveness. (PN)