Financier Zalman Bernstein left the bulk of his charitable wealth to the discretion of his wife, Mem Bernstein, and his longtime friend and confidante, Arthur Fried. This is the history of how they used that legacy to create a unique Jewish high school in San Francisco, publish books on prominent Jewish topics, create an influential online newsmagazine, improve education and promote Jewish culture in Israel, and provide for disadvantaged Jewish children in the former Soviet Union, among many other causes.

When the billionaire financier Sanford C. Bernstein experienced a religious awakening in his mid-50s, he went on not only to live a more dedicated Jewish life (and change his name to Zalman Chaim Bernstein), but to use his charitable giving to promote Jewish learning, culture, solidarity, and continuity around the world. After he died in 1999, his two charitable trustees — his wife, Mem, and his longtime friend and adviser, Arthur Fried — established a new philanthropy, called Keren Keshet – The Rainbow Foundation. Applying their own entrepreneurial style of philanthropy, they backed strong Jewish leaders and organizations in the U.S., Israel, and the former Soviet Union, and launched whole new enterprises, including the innovative Jewish Community High School of the Bay and the influential online newsmagazine Tablet. This is the story of how two dedicated Jewish donors, with minimal staff and no bureaucracy, enriched the Jewish world with nearly $300 million in grants.