"Voice" is widely considered to be a feature of effective writing. It's no surprise, then, that voice criteria frequently appear on rubrics used to score student essays in large-scale writing assessments. However, composition theorists hold vastly different views regarding voice and how it should be applied in the evaluation of student writing, if at all. Further, given that clear voice definitions are notoriously elusive, research on the importance of voice in writing evaluation is inconclusive, and to date no study has examined how writing evaluators apply voice criteria. Because conceptualizations of voice in composition literature often vary according to genre, this study examines relationships among voice criteria, writing quality, and genre. I investigate voice within the context of large-scale secondary writing assessments because such assessments provide formal and influential articulations of how voice is instantiated as an assessment criterion. Three questions are addressed in three interrelated studies: (1) In what ways and to what extent are voice criteria associated with genre demands in large-scale writing assessment designs? (2) What language features do secondary English teachers associate with voice, and how do such identified features vary across genres as well as among readers? (3) To what extent do voice-associated features map onto the lexical features that differentiate high from low scoring student writing samples of different genres? These questions are examined using three complimentary methods: (1) a content analysis of prompts and rubrics from U.S. exit-level direct writing assessments; (2) an inductive analysis of teacher interviews regarding their perceptions of voice in narrative and expository writing samples; and (3) a quantitative analysis of high and low scoring "benchmark" papers. The results of these integrated studies raise not just questions, but paradoxes about the consistency and transparency with which voice criteria can be applied to writing assessment in practice. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]