When they were still in their twenties, Cari Tuna and her husband, Facebook co-founder Dustin Moskovitz, found themselves among a handful of the world’s youngest billionaires. In 2010, Tuna and Moskovitz became the youngest donors to sign the Giving Pledge, a campaign begun by Bill Gates and Warren Buffet to encourage the world’s billionaires to give away the majority of their wealth to charity.

Tuna knew that she wanted to share her wealth with the world’s neediest people. And she wanted her impact to be substantial and effective.

In her first major press interview with the Washington Post, Tuna cites Peter Singer’s 2009 The Life You Can Save as the book that energized her own quest to give back—and to give back effectively.

Early in her research, Tuna came across Peter Singer’s “The Life You Can Save” — a book she cites as the catalyst for their approach. An Australian philosopher, Singer makes the moral case for giving, arguing that many people in the developed world can do so at little cost to themselves.

The Life You Can Save inspired Tuna and Moskovitz to launch Good Ventures. Over the last three years, they’ve given away $45 million dollars through the foundation.

The foundation capped off 2014 by announcing that eight of The Life You Can Save’s recommended charities had been awarded grants for 2015.

GiveDirectly, Evidence Action’s Deworm the World Initiative, Schistosomiasis Control Initiative (SCI), Against Malaria Foundation (AMF), Development Media International, Living Goods, Global Alliance for Improved Nutrition, and Iodine Global Network won end-of the-year grants from Good Ventures totaling over $19 million.

What’s on your reading list for 2015? Check out The Life You Can Save to learn what inspired Cari Tuna to give—and to give back effectively.