Researchers have reported that preservice mathematics teachers' (PMTs') conceptions for radian angle measure are dominated by conceptions of degrees, memorization, and calculational strategies, and are always expressed in terms on [pi]. In this report, I unpack the mathematical meanings of a PMT, Henry (pseudonym), as he engaged in three task-based interviews involving radian angle measure. In the first interview, Henry described radians procedurally, emphasizing memorized special angles written in terms of [pi]. By the end of the final interview, Henry described radians conceptually, including generalizing special angles. I conclude by highlighting the importance of tasks designed to build and support conceptual understanding. [For the complete proceedings, see ED658295.]