This article argues that most variants of professional development in information and communications technologies are merely "in-between" processes, the design of which does not pay sufficient attention to important antecedent and post-engagement activities. These we identify as preparing the ground before the main engagement with the teachers begins, and enabling teachers to make and sustain their own progress after it is complete. Using two empirical case studies, this article sets out to explore, from a primarily UK perspective, the two-fold process of "striking the chord" of teachers' interest and commitment as precursors to change, and pursuing sustainability once the face-to-face role of conventional professional development has ended. (Contains 2 figures.)