Laura Arrillaga-Andreessen speaks onstage on October 9, 2014 in San Francisco, California. (Kimberly White/Getty Images for Vanity Fair)

Laura Arrillaga-Andreessen is at the hub of the Silicon Valley philanthropy world.

A Stanford University lecturer and author of the bestseller “Giving 2.0,” she has a calendar full of coffees and lunches with some of the tech industry’s heaviest hitters: Meg Whitman, Brian Chesky, and husband-and-wife teams Mark Zuckerberg and Priscilla Chan and Dustin Moskovitz and Cari Tuna.

She’s the person who persuades the young billionaires to give away their wealth now, not later.

“Laura is always encouraging me to do more with our giving and do it better,” said one of her best friends, Anne Wojcicki, the head of personal genetics company 23andMe and the estranged wife of Google co-founder Sergey Brin. Wojcicki has given several hundred million dollars to charities such as Ashoka, a network of social entrepreneurs, and Tipping Point Community, a Northern California group that seeks to eliminate poverty. Yet philanthropy still comes up a lot when the two get together.

Arrillaga-Andreessen, 44, was rich long before she met and married Netscape founder Marc Andreessen in 2006. Her father is billionaire Silicon Valley real estate magnate John Arrillaga Sr. But she grew up modestly, got a $750 used Honda as her first car and says she didn’t know the family was wealthy until her father’s name landed on the Forbes 400 list during her junior year of high school.

She was about to go to Stanford’s business school, after getting bachelor’s and master’s degrees in art history, when her mother was diagnosed with terminal lung cancer. Frances C. Arrillaga, a longtime philanthropist, was 52. Her daughter moved home to care for her until her death, and that experience made her want to dedicate her life to helping others.

Since then, she has worked with tech industry peers to develop innovative models for giving that she said she hopes will transform the world in ways as profound as the Internet, which gave rise to much of the new wealth in Silicon Valley.

Arrillaga-Andreessen believes in philanthropy that is proactive rather than reactive. She said that many people tend to give in the moment, when they hear news about natural disasters or see a picture that moves them. “But feeling good in the moment doesn’t necessarily accomplish our greater goal — making the world a better place,” she writes in her book.

“Too often the warm glow that drives us to give is not backed by knowledge, research, and strategy.”

“As you probably already know,” she adds, “giving away money is easy — doing so effectively is much harder.”

This interview, the first in a series of conversations with Silicon Valley figures who are shaking up philanthropy, has been edited for length and clarity.

Many of Silicon Valley’s young stars who are just starting out with their philanthropy have come to you for advice. What do you tell them?

Philanthropy is at its most meaningful when people are actualizing one of their greatest personal passions — whether it’s intellectual, emotional or spiritual. For anybody who wants to express their generosity in a way that matters, we have the responsibility to look at the market and ensure our generosity is being translated into helping organizations or systems who would not otherwise be helped.

Why do you think so many have directed their philanthropy at science and medicine?

Those are the fields we grew up feeling at home in, and they are of great intellectual interest because they are incessantly evolutionary, and that’s what Silicon Valley is all about.

What are some other big areas where technologists are directing donations?

The use of technology — to democratize access to so many things people in this country have the blessing to call our basic human rights, whether that’s freedom of expression, access to education [or] medical care, knowledge or being a part of the global economy. There is great interest in Silicon Valley in how we can use technology to break down the barriers to access that so many billions of people in the world face.

That and entrepreneurship. We’re seeing a trend of hybridization of entrepreneurship and social entrepreneurship that individuals are excited about investing in. Whether it’s investing in for-profit companies that have social value creation inherent in their business models or nonprofits that have revenue generation that will lead to financial self-sustainability for nonprofits.

Through your own philanthropy, you’ve supported local police departments, veterans services as well as health care. One of your largest gifts — and first major one with your husband — was a $27.5 million donation to Stanford Hospital & Clinics to build a state-of-the-art emergency-care facility. What motivated you to make this investment?

We wanted to make a gift where there would be a direct impact. Our approach entails a significant amount of actual services and meeting the immediate needs of people who have emergency medical needs and also to help with pre-hospital training and disaster training.

You’ve advocated for more transparency in philanthropy. Why do you think this is important?

We in the philanthropic sector need to operate not just with glass pockets but glass skulls.

What I mean by that is we need to be transparent publicly about where it is we are giving our money. But that’s only the first step. Of equal, if not even greater, importance, we need to be transparent about why we made the decisions we made so that other people can benefit from that research as well.

Because ultimately it is that knowledge-sharing that enables both the positive influence to fund as well as an also positive influence not to fund specific nonprofits.

Every time we make a gift to one organization, we’re simultaneously deciding not to give, indirectly, to countless other organizations. By sharing why we’re making those decisions, we’re enabling other people to direct their resources in a more informed way as well. By having glass skulls, we’re breaking down the intellectual silos in which philanthropy has traditionally operated.

How does the approach taken by younger philanthropists differ from the previous generation? How popular is the idea of “effective altruism” — using empirical research over instinct and emotion to make decisions about giving — among those you are advising?

It’s an area many millennials are passionate about. It’s a generation that has grown up with a sense of global community and awareness that transcends traditional geographic boundaries and also a group that has become grown-ups with data as a key driver of decision-making. Those two external influences naturally lead many individuals to sharing that particular philanthropic approach.

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