Although not all the problems of writing are solved by practice in letter writing, a review of the classical texts on "ars dictaminis"--letter writing--creates a strong argument for its increased use as an exercise in college composition classrooms. By incorporating the lessons of dictamen as a device for achieving rhetorical modes--narration, description, exposition, argumentation, or whatever set of rhetorical goals are used--students will progress with less difficulty from loose oral thinking to logically ordered written thought. Further, many students who face writer's block can achieve confidence when directed away from teacher as audience to someone of their choice. Also, they will realize the effectiveness of different levels of usage as they change audience, topic, and purpose for writing. Moreover, by the simple mechanical device of having to determine audience, the writer unconsciously achieves tone. The mechanical necessity of putting name to letter also apprises the student of the importance of being clear and correct. Grammar, style, and rhetoric are integrated, as is the rhythm of the language. Finally, the practicality of writing letters appeals to the students, for whatever their chosen professions, they know that they will always write letters. In short, the classical mandates of completeness, clarity, conciseness, and logic take on personal significance when students are asked to write letters. (RL)