Looking back from the year 2100, we'll see a period when our creations -- technological, social, ecological -- outstripped our understanding and we lost control of our destiny. And we will think: if only -- if only we'd had the ingenuity and will to prevent some of that. I am convinced that there is still time to muster that ingenuity -- but the hour is late.

The challenges facing human societies -- from international financial crises and global climate change to pandemics of tuberculosis and AIDS -- converge, intertwine, and often remain largely beyond our understanding. Most of us suspect that the "experts" don't really know what's going on, and that we've released forces that are neither managed nor manageable. This is the "ingenuity gap," the term coined by Thomas Homer-Dixon, renowned political scientist and sometime adviser to the White House: the critical gap between our need for practical and innovative ideas to solve our complex problems and our actual supply of those ideas.

He shows us how, in today's world, while poor countries are particularly vulnerable to ingenuity gaps, our own rich countries are no longer immune, and we are all caught dangerously between a soaring requirement for ingenuity and an increasingly uncertain supply. As the gap widens, political disintegration and violent upheaval can result, reaching into our own economies and daily lives in subtle, unforeseen ways. In compelling and lucid prose, he makes real the problems we face and suggests how we might overcome them -- in our own lives, our thinking, our businesses, and our societies.