To date there has been little research into how do-it-yourself (DIY) corpora can effectively be used in DDL courses in professional ESP contexts with undergraduate students. This chapter reports on the design, outcomes and value of a course integrating corpus compilation and consultation for undergraduate students of ESP. The chapter introduces some core principles of course design for corpus-based ESP courses, arguing that approaches proposed by CALL research should be incorporated in corpus-based courses. Data was collected by means of analysis of written student reports and questionnaires administered immediately after the course and five months after the end of the course. Findings reveal that all students found corpus use beneficial for ESP learning. They especially valued corpora for writing, expanding their vocabulary in general and learning subject-specific terminology. A third of the students mentioned specific plans to use corpora in the future in their reports and a great majority of students reported having used online available corpora five months after the course. It is suggested that the process of compiling their DIY corpora may have enhanced their understanding of the nature and limitations of corpus data and thus helped them interpret corpus output more accurately
