Forty years ago, Bill and his childhood friend Paul Allen bet that software and personal computers would change the way people around the world worked and played. This bet wasn't exactly a wager. It was an opportunity to make computers personal and empower people through the magic of software. Some people thought they were nuts. But the bet turned out well.

Fifteen years ago, the two of us made a similar bet. We started our foundation in 2000 with the idea that by backing innovative work in health and education, we could help dramatically reduce inequity. The progress we've seen so far is very exciting — so exciting that we are doubling down on the bet we made 15 years ago, and picking ambitious goals for what's possible 15 years from now.

OUR BIG BET The lives of people in poor countries will improve faster in the next 15 years than at any other time in history. And their lives will improve more than anyone else's.

WE SEE AN OPPORTUNITY AND WE WANT TO MAKE THE MOST OF IT. We're putting our credibility, time, and money behind this bet — and asking others to join us — because we think there has never been a better time to accelerate progress and have a big impact around the world. Some will say we're irrational to make this bet too. A skeptic would look at the world's problems and conclude that things are only getting worse. And we shouldn't lose sight of the fact that a handful of the worst-off countries will continue to struggle.

But we think the next 15 years will see major breakthroughs for most people in poor countries. They will be living longer and in better health. They will have unprecedented opportunities to get an education, eat nutritious food, and benefit from mobile banking. These breakthroughs will be driven by innovation in technology — ranging from new vaccines and hardier crops to much cheaper smartphones and tablets — and by innovations that help deliver those things to more people.

The rich world will keep getting exciting new advances too, but the improvements in the lives of the poor will be far more fundamental — the basics of a healthy, productive life. It's great that more people in rich countries will be able to watch movies on super hi-resolution screens. It's even better that more parents in poor countries will know their children aren't going to die.

It is fair to ask whether the progress we're predicting will be stifled by climate change. The most dramatic problems caused by climate change are more than 15 years away, but the long-term threat is so serious that the world needs to move much more aggressively — right now — to develop energy sources that are cheaper, can deliver on demand, and emit zero carbon dioxide. The next 15 years are a pivotal time when these energy sources need to be developed so they'll be ready to deploy before the effects of climate change become severe.

Bill is investing time in this work personally (not through our foundation) and will continue to speak out about it. We're excited to see how much better the world will be in 15 years. Here are some of the breakthroughs we see coming.