English for Academic Purposes (EAP Writing) is a compulsory course for English literature and language students at Obirin University. The first semester focuses on expository writing, typical of the TOEFL[R] writing exam. The second semester focuses on writing about literature. To facilitate their writing all students are provided with a user account for Criterion, a web-based essay management system. Essays submitted to Criterion are evaluated by computer, and returned to the writer in approximately one minute. Submitted essays are kept on the Criterion server, where they can be accessed and evaluated by teachers, and further revised by students. This paper will present an overview of the Criterion essay management system in the context of an English for Academic Purposes (EAP) Writing course. We will discuss student and teacher productivity, providing feedback on student writing, using corpus linguistic techniques in conjunction with Criterion, and learning outcomes. (Contains 1 table.) [This paper was published in: Gutierrez, T. (Ed.), Glocalization through CALL: Bringing People Together. JALTCALL 2005 Proceedings. The Japan Association for Language Teaching Computer Assisted Language Learning Special Interest Group (JALT CALL SIG), 2006. p141-145.]