Current interest in performance assessment in education raises many measurement questions, one of which is concern for the validity and usefulness of holistic ratings versus multiple-dimension ratings of student work. A study of more than 10,000 students in Grades 3 and 8 was conducted to explore the advantages of analytical scoring in writing assessment. Trained readers scored student essays on a 6-trait analytical scoring system. Cluster analyses were employed to identify subgroups of students who showed similar patterns of trait scores. Eleven patterns of student scores, reflecting different patterns of strengths and weaknesses in writing, were replicated across five modes of writing (e.g., descriptive and persuasive). Limitations of the study and implications for performance assessment are discussed.