Foucault gets the ball rolling with an interesting comparison of research and teaching:
"I would like us to be a bit clearer about what is going on here, in these lectures. You know that the institution where you are, and where I am, is not exactly a teaching institution...we are paid to do research. And I believe that, ultimately, the activity of teaching would be meaningless unless we gave it, or at least lent it, this meaning, or at least the meaning I suggest: Given that we are paid to do research, what is there to monitor the research we are doing? How can we keep informed people who might be interested in it, or who might have some reason for taking this research as a starting point? How can we keep them informed on a fairly regular basis about the work we are doing, except by teaching, or in other words by making a public statement? So I do not regard our Wednesday meetings as a teaching activity, but rather as public reports on the work I am, in other respects, left to get on with more or less as I see fit."
In the academic world, teaching and research have an uneasy relationship. Officially, of course, we have distinctions between "Research I" institutions and down the line to liberal arts colleges, and the common way to talk about schools is whether they're research or teaching focused (and to tailor our job letters toward each school's emphasis). However, no matter where you are, you're generally expected to do at least a little of both teaching and research.
Foucault's position is interesting in part because he at first seems to equate teaching with "making a public statement," but then immediately pulls that back in the next sentence by admitting he doesn't consider the lectures "a teaching activity, but rather public reports" on his research. This contradiction can in part be explained by the fact that Foucault is really providing something as straightforward as a report on his current research interests, but that since his research is so remarkably original even that report provides insight and guidance to the audience.
Part of the usefulness of the lectures is simply the connections he makes, tracing the development and divergences of concepts like "nation," "state," "race," "class," and "society," especially as they relate to the workings of power.
I can't say it's the easiest reading I've ever done, but I've got to re-dedicate myself to the academic life and I'm thinking these bite-size lectures are a good way to begin.