This chapter provides an overview of measures of second language (L2) production that have been used to index learners’ engagement in pedagogic task performance in task-based language teaching (TBLT) research. The chapter provides a basis for using discourse analytic methods in research on the role of the learner in L2 task performance. The advantages and limitation of discourse analytic methods are discussed, and it is suggested that these methods are most informative when complemented with additional measures, including the emerging methods discussed in subsequent chapters. The chapter closes with suggestions for the use of discourse analytic measures within a broader research agenda on the conative and affective dimensions of TBLT research.