I'm in the midst of "re-reading" (more about those quotation marks later...) Michael Lipsky's 1980 classic Street Level Bureaucracy: Dilemmas of the Individual in Public Service. It's just been re-released with an extended update section at the end.
What is particularly powerful for me about it is, because it systematically goes through the contradictions and problems in bureaucrats lives, it offers a very effective critique of managerial and market solutions to the problems of policy implementation.
I have very little time for applying economic analysis to bureaucracies, or treating public services as if they are in a market, because they're not. The market has failed and therefore you have public services. Lipsky applies market analysis, but in a very constructive way, and reveals why you should not apply economics to bureaucracies. For example, when he asserts that demand for public services will grow with supply, this is economic fact. But it is then used to illuminate why bureaucrats are therefore not market actors. They are pragmatic decision-makers who struggle to make good decisions on the hoof.
I also have very little time for managerialism, from the left or right, that purports that if we just manage bureaucracies right then all will be well. Lipsky's analysis demolishes this concept. Bureaucracies just contain too many inherent contradictions for management to ever "rationalise" them away.
As such, what impresses me about the book is I think it offers for public policy what Adam Smith's The Wealth of Nations offers to micro-economics - a bloody good explanation of what is going on out there.
If you're interested, see this youtube video that popped up on a google search.
Now, those quotation marks. I did reference the book in my thesis very loosely. Actually, back then I'd just read the introduction, conclusion and a few pages in between. I tweeted this and discovered I'm not alone in the naughty behaviour. Anyway, I'm making up for it now by reading the thing, and I'm very glad too. Here's hoping my external examiner doesn't read this!