The natural resources are the biggest opportunity for rapid development that many poor countries have. And the supercycle of the last ten years has been the biggest opportunity that they've had in history. And for most of them, it's been a missed opportunity. And so it's really important, society by society, to discover what went wrong and what is needed to be understood in order for next time to go better. And there will be a next time. So, I'm giving two lectures. One will look at the challenge of discovering natural resources, getting them out of the ground, and getting them into revenue. The next lecture will look at what you do when you've got revenues, turning them into something that is sustainable. Because the revenues themselves are only temporary. If we look at what went wrong during the supercycle, most of the problems occur in that second half. It's using revenues for sustained development. And so, of the two lectures I'm giving, the more import...