Comparing the three version of Ælfric'sColloquy, the essay argues that Ælfric's student Ælfric Bata made editorial additions to each version. These interpolations are presented in detail, and probable teaching aims behind the changes are explored. Bata's possible authorship of the continuous gloss to theColloquy is also suggested. Textual evidence from relevant manuscripts allows a comprehensive description of Bata's editorial and authorial activities, and furthermore establishes his close connection with MS. Oxford, St John's College 154, a connection which may indicate Bata's involvement in the publishing of Ælfric's influential pedagogical works.