One of the things that I find very effective both from the perspective of the instructor and the perspective of the student is personal experience. When discussing a concept in either synchronous or asynchronous contexts, the instructor can introduce situations in which he or she has been personally involved (from a professional standpoint). Students participating in either type of discussion can also share experiences with a particular concept. Both of these additions to the discussion help underscore the essence of concept introduced in that part of the course.