This paper explores the potential of a poststructuralist and rhetorical analysis in appreciating more fully the discursive work of assessment tasks as mechanisms of power/knowledge within discourses of professional development. It is argued that such analysis may reveal detail in the way in which assessments work as material elements within a body politic, and what they attempt in the investment and positioning of bodies as subjects and objects of knowledge. The paper examines in detail the work of two assessment tasks from an in-service programme of professional development for further education lecturers in Scotland to see what can be said of their rhetorical accomplishment. Analysis shows the devices and techniques at play. Such analysis may offer educators an alternative discourse to explore the effects of the assessment tasks that they set for their students.