I don't remember offhand the specifics of the AECL chair, but we normally run a selection process for chairs and CEOs. We announce the position and receive applications. We have a selection committee that considers the applications, conducts interviews, and makes a recommendation to the minister on those who are qualified for the position. The minister then makes a determination on which one he or she wants to recommend to cabinet.
On March 4th, 2008. See this statement in context.