Here are some recent results:

In the first study of its kind, Chhatre and Arun Agrawal of the University of Michigan
in Ann Arbor compared forest ownership with data on carbon
sequestration, which is estimated from the size and number of trees in
a forest. Hectare-for-hectare, they found that tropical forest under
local management stored more carbon than government-owned forests.
There are exceptions, says Chhatre, "but our findings show that we can
increase carbon sequestration simply by transferring ownership of
forests from governments to communities".

One reason may be that locals protect forests best if
they own them, because they have a long-term interest in ensuring the
forests' survival. While governments, whatever their intentions,
usually license destructive logging, or preside over a free-for-all in
which everyone grabs what they can because nobody believes the forest
will last (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0905308106).

The authors suggest that locals would also make a better job
of managing common pastures, coastal fisheries and water supplies. They
argue that their findings contradict a long-standing environmental
idea, called the "tragedy of the commons", which says that natural
resources left to communal control get trashed. In fact, says Agrawal,
"communities are perfectly capable of managing their resources
sustainably".

If you turn to the first page of the paper itself, the header reads:

Edited by Elinor Ostrom, Indiana University, Bloomington, IN, and approved September 4, 2009 (received for review July 22,
2009)

Of course this sort of result is inspired by her work as well.  For the pointer I thank Andrew Grant.

That's his greatest contribution (see Alex on this same point, and Jeff Ely).  Let's say you privatize a water system in Africa and write a 30-year contract with a private French company to run the thing.  As the contract nears its end, and if renewal is not obvious, the company has an incentive to "asset strip," or at the very least not maintain the value of the pipes.  Alternatively, the government might signal, in advance, that it has every intention of renewing the contract.  The company then has the incentive to lower quality to consumers, since it expects renewal a and faces weaker competitive constraints.

In other words, franchise bidding, or "ex ante" competition for the market doesn't always resolve monopoly issues  The key problem is the existence of a fixed investment in the pipes and that the value of the pipes depends on investments from both the government and the company.  It can be hard to write a contract for a good solution, since any allocation of the residual rights creates some distortion or another.  This has in fact been a very real problem with privatization around the world in many settings.  Oliver Williamson outlined these arguments in his debate with Harold Demsetz over privatizing cable TV.  Much of the literature on "mechanism design," such as David Baron's pieces, picks up on this problem and extends Williamson's work.

Williamson is a truly important economist.  If you read him, especially in his later work, he also has lots of taxonomy and verbiage.  The key is to cut through to the substance, which is plentiful.

Here is John Nye on the Prize. 

Whoops!  Usually today I'm supposed to stay home and cover the winner of the economics Nobel Prize.  But I'm on a plane home from Paris as the prize is announced and I am not landing for many hours.

Alex may well provide coverage of his own, but in the meantime please leave your discussion and analysis here in the comments.

I remember last year when one reporter at a prominent newspaper said to me: "If it's Lars Hansen you *are* going to explain to us what he did in plain English, right?"  Well…if Lars is going to win it, here's hoping that this is the year.