One of the least examined forms of school/university collaboration is that which brings together scholars in a given discipline and teachers in the corresponding school subject. The paper investigates four summer institute sites of the California History Social Science Project, focusing on the language used by historians and teachers to describe their own and each other’s roles and contributions. The study reveals two sets of discourses. The first involves the notions of 'content' and 'pedagogy.' Although these terms seem to level the playing field of professional authority between discipline-based professors (as 'content experts') and teachers (as 'pedagogy experts'), they provide a problematic, fundamentally technical model of history teaching and learning. The second, revolving around 'doing the discipline,' provides a far more satisfactory account of, and trajectory for, collaborative professional work aimed at teaching and learning for understanding. (http://www.tandfonline.com/doi/abs/10.1080/002202799183151)