This article describes the just-in-time online professional development offered to teachers in the Remote Networked Schools (RNS), a systemic initiative funded by the Quebec Ministry of Education (Canada), which aims at enriching the learning environment of small rural schools with the use of information and communication technologies (ICTs). The design experiment method studies the activity identified and the types of professional development offered by a university-based intervention team (UBIT) over six years of deployment. (Contains 4 tables, 4 figures and 5 footnotes.)