Writing is a highly complex ability developed over years of practice, across a wide range of tasks and contexts, and with copious, meaningful feedback. As the Common Core State Standards (CCSS) sweep into individual classrooms, they bring with them a renewed sense of the importance of writing to students' education. Research on the assessment of student writing consistently shows that high-stakes writing tests alter the normal conditions of writing by denying students the opportunity to think, read, talk with others, address real audiences, develop ideas, and revise their emerging texts over time. Concerns -- increasingly voiced by parents, teachers, school administrators, students, and members of the general public -- are intensified by the use of machine-scoring systems to read and evaluate students' writing. To meet the outcomes of the Common Core State Standards, various consortia, private corporations, and testing agencies propose to use computerized assessments of student writing. The attraction is obvious: once programmed, machines might reduce the costs otherwise associated with the human labor of reading, interpreting, and evaluating the writing of our students. Yet when considered what is lost because of machine scoring, the presumed savings turn into significant new costs -- to students, to our educational institutions, and to society. This position statement presents the view of National Council of Teachers of English (NCTE) on machine scoring, along with ideas for alternative approaches. An annotated bibliography is included. [This statement was prepared by the NCTE Task Force on Writing Assessment.]