Consider the force of this situation: under development will be the greatest production tool in history, a truly general fabrication system able to make anything that can be designed - and a design system will already be in hand. Will everyone wait until assemblers appear before planning how to use them? Or will companies and countries respond to the pressures of opportunity and competition by designing nanosystems in advance, to speed the exploitation of assemblers when they first arrive?

How well we design ahead - and what we design - may determine whether we survive and thrive, or whether we obliterate ourselves.

Medical technology, the space frontier, advanced computers, and new social inventions all promise to play interlocking roles. But the assembler breakthrough will affect all of them, and more.