To celebrate the launch of TIME’s new multimedia project – 100 Photographs: The Most Influential Images of All Time – we asked leaders in a number of fields, from technology to the arts to business, to share the single photograph that most influenced their lives. Purchase the 100 Photographs book now.

Poverty as a category of analysis is an abstraction. But poverty as it is lived by more than a billion people is as concrete as it gets. This haunting photograph—and in particular Florence Owens Thompson’s eyes—capture that hard reality better than any image I’ve seen. I studied this picture way back in high school, and even though I’ve spent years doing anti-poverty work around the world, Mrs. Thompson’s eyes—sad, uncertain, yet somehow brave and full of resolve—still come to mind when poverty is the topic of conversation.

Melinda Gates is co-chair of the Bill & Melinda Gates Foundation.