Bill and Melinda Gates’ names are practically synonymous with philanthropy. For 18 years, the couple have been putting their enormous wealth to work in some of the most deprived parts of the world through their Foundation — tackling preventable diseases, alleviating famine, and improving education access for all. 

In total, according to the Foundation website, it has given more than $40 billion in grants to developing countries and within the US. And every year, they publish a letter about their work, about the lessons they’ve learned, and highlighting some of their biggest priorities for the year to come. 

But this is a special year for the Gates, as this is the 10th year that they’ll have published this important letter. 

Be the first to read @BillGates & @MelindaGates' 2018 Annual Letter. https://t.co/IYRD0NxQIEpic.twitter.com/xdyTYIZLGJ

— Gates Foundation (@gatesfoundation) February 13, 2018

So, to celebrate, the pair have revealed — and answered — 10 of the toughest questions they get asked, by journalists, business leaders, governments, and members of the public. 

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And they’re right, these are really tough questions — they address why they don’t give more money in the US, why they don’t give money to fight climate change (short answer, they do), and how President Trump’s policies affect their foundation’s work. 

We’re not going to give it all away — no spoilers, you can find the full letter here — but here are just a few of our favourite questions and answers. 

1. What Happens When You Disagree? 

Melinda highlights this as a question she gets asked all the time, but Bill practically never does.

“Sometime’s it’s from journalists hinting that Bill must be the one making the decisions,” she writes. “Other times, it’s from women philanthropists asking advice about how to work more effectively with their husbands.” 

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She writes that she and Bill have two main things going in their favor. 

“First, we agree on basic values. For our wedding Bill’s parents gave us a sculpture of two birds side by side, staring at the horizon, and it’s still in front of our house. I think of it all the time, because fundamentally we’re looking in the same direction.” 

Her second point, is that Bill is very open-minded.

“When I tell a story about what I’ve seen, he feels it,” she writes. “He might ask me to gather some data for good measure, but he doesn’t doubt the reality of my experiences or the soundness of my judgment.”

2. Why Are You Really Giving Your Money Away — What’s in It for You?

The Gates have given an extraordinary amount of money to charity. In August last year, Bill donated $4.6 billion worth of Microsoft shares — his biggest donation since 2000 — which took the couple's total charitable donations to around $50 billion, reported CBNC. 

But, according to Bill, they don’t do the work that they do in the hope that one day they’ll be remembered. 

“We would be delighted if some day diseases like polio and malaria are a distant memory,” he writes, “and the fact that we worked on them is too.” 

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But, he adds, their main motivation is the fact that it’s “meaningful work,” and they have fun doing it. He writes that it’s very rare to be able to find a job where you get to both have a big impact and a lot of fun, but it’s something that he has experienced both with Microsoft, and with the Foundation. 

And as to why they give their money away…

“We think that’s a basic responsibility of anyone with a lot of money,” writes Bill. “Once you’ve taken care of yourself and your children, the best use of extra wealth is to give it back to society.” 

“We both come from families that believed in leaving the world better than you found it,” adds Melinda, who points out that, of course, their values are far from unique to themselves.

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“Millions of people give back by volunteering their time and donating money to help others,” she writes. “We are, however, in the more unusual position of having a lot of money to donate.”

She writes: “Our goal is to do what our parents taught us and do our part to make the world better.” 

3. How Do You Stay Optimistic? 

This isn’t actually included in the 10 questions, but is addressed in the letter, so we thought we’d include it as a bonus question — mainly because it’s something everyone should hear. 

It’s also a question, according to the Gates, that is being asked more and more. 

And their answer is quite simple — that, despite the headlines being filled with awful news, they see a world that is getting better. 

Read more: How Powerful Is the 'Me Too' Movement? Melinda Gates Says It Could Change the World

They cite the falling death rate of children — which has been halved since 1990 and keeps falling. They say the number of mothers who die has also dropped dramatically. 

Extreme poverty has fallen by nearly half in just 20 years; and more children are attending school. And the list goes on, they add. 

“But being an optimist isn’t about knowing that life used to be worse,” they write. “It’s about knowing how life can get better. And that’s what really fuels our optimism.” 

Read more: How Bill Gates Is Helping Lift 100 Million Farmers Out of Poverty

“Although we see a lot of disease and poverty in our work — and many other big problems that need to be solved — we also see the best of humanity,” they continue. “We spend our time learning from scientists who are inventing cutting-edge tools to cure disease. We talk to dedicated government leaders who are being creative about prioritizing the health and well-being of people around the world.”

“And we meet brave and brilliant individuals all over the world who are imagining new ways to transform their communities,” they add.

Well said! 

Global Citizen campaigns to achieve the UN’s Global Goals and end extreme poverty by 2030. We campaign against preventable diseases, gender discrimination, hunger, and poor sanitation, and to alleviate the suffering of the world’s most vulnerable people. You can join us by taking action on these issues, and more, here. 

Disclosure: Global Citizen receives funding from the Bill and Melinda Gates Foundation.