What is the most important engineering problem of our future?

[Ken Leung]

In an attempt to learn more about Engineering and becoming an Engineer, I would like to ask all the Engineers in this community this question:

What is(are) the most important engineering problem(s) we are going to face in the near future?

FIRST has done a tremendous job inspiring kids to become Engineers through the competition. But how about educating them with something that relates to the real world? How about telling us what kind of problems we will be facing when the next group of college students graduate and become Engineers? What is the most important engineering problem(s) we should expect to face in the next 10 years? 20 years? 50 years? 100 years?

I do realize that "most important" means different things to different people, so let's broaden the discussion up and extend its definition as wide as possible. I don't care whether it is the most expensive, the most difficult, the most beneficial, the most demanding, the most impossible, and so on, as long as it is big enough to make us go "Wow..." Just surprise me ;-).