When he got offered a job at the technology company EarthLink, Tom Hsieh hesitated.

Could he start early and leave at 3 p.m.?, he asked his would•bebosses. They looked at him with bemusement. This was the mid-1990s, when working in high-tech often meant ordering in pizza and sleeping at the office. But Mr. Hsieh, who’d become committed to Christian ideals of serving the poor as a college student, explained that he needed to be home early so he could tutor neighborhood kids in this Southern California town where he still lives.

Mr. Hsieh, 39, got the job—and a promotion a few months later, his income eventually rising to $250,000. Yet he does feel a tension between the business world he channels through his BlackBerry and his personal and spiritual life. He and his wife, Bree, 34, live at the median household income level (now about $50,000) and give the rest of their money away.

“You’re a little amphibious, a little bicultural,” says Ms. Hsieh, of inhabiting two socioeconomic groups.

Mr. Hsieh smiles at himself as he tells a story about rolling up to a business dinner at a Ritz-Carlton hotel in his 1991 Chevrolet Geo Metro and watching the valets laugh at him.

A Fuller Life

But the Hsiehs say their decision reminds them of how fortunate they are and allows them to lead a fuller life. In addition to giving them deep satisfaction, the Hsiehs say that living modestly and among people they seek to help enables them to fight poverty more effectively. “If you live in a different community, these things don’t matter to you in the same way,” says Ms. Hsieh.

Mr. Hsieh helped to start a nonprofit affiliated with their church, Pomona Hope Community Center, which runs after-school programs, a community garden, and job-training programs. Ms. Hsieh has a job in communications for Servant Partners, a Christian missionary group with headquarters in Pomona, which works in slums in the United States and overseas. The Hsiehs met after college, through an internship program with the group, and they support it today.

The couple recalls how they have held meetings of their neighbors that have resulted in people stepping up and seeking change. With the Hsiehs’ help, local residents persuaded the City Council to direct $1.2-million for 500 new streetlights and secure a bond to pay for air conditioning at a local school.

“It brought forth new community leaders,” says Mr. Hsieh. “People could no longer just complain or feel like they’re powerless.”

But the Hsiehs say many nonprofit efforts, both in the United States and abroad, don’t focus on the grass roots. They say too many aid organizations seem to take a paternalistic approach and sometimes even make things worse.

Mr. Hsieh cites an example of child-sponsorship programs that spawn competition among families who want their children to find a sponsor so the family can live off that money. “That’s part of their economic strategy,” he says.

That frustration led Mr. Hsieh and other community members, including some retired employees of large international•development ations, to create a new global antipoverty nonprofit, Millennium Tools. The group is small and hasn’t settled on its approach, but its goal is to bring together businesses, community organizers, international-development experts, and philanthropists to share their knowledge.

No Mercedes-Benz

The Hsiehs live with their 3-year-old daughter in a two-bedroom, two-bathroom duplex that they rent for $1,000. A $6 print hangs above the kitchen table. While both of their families are religious, they didn’t immediately embrace their childrens’ decision to live so modestly.

Ms. Hsieh’s parents, who were living in North Dakota, were at first worried about her safety in South Central Los Angeles, where she lived when she met Mr. Hsieh, as well as in Pomona.

Mr. Hsieh’s parents, who are from Taiwan, were impressed by the salary he was making and didn’t understand why he would want to give it all away. But they came to accept his decision, he says, even if it meant that he wasn’t going to “be the Chinese son who can buy the Mercedes-Benz so you can show it off to your friends.”

A ‘Check on Reality’

But the couple had to cut back on their giving three years ago, when Mr. Hsieh left EarthLink to start his own information-technology company, SplinterRock, with another alumnus of Servant Partners. Ultimately, the business partners hope the company can give more than they were giving individually. The company lets its clients designate 30 percent of their payments to SplinterRock to the charity of their choice.

But in these early years, the start-up company has reduced Mr. Hsieh’s ability to give. He just recently gave himself a raise, to $70,000.

Mr. Hsieh says giving less has been difficult because his generosity had become so much a part of his identity. He has told his story at churches, conferences, and other events, sometimes at the behest of Bolder Giving, a New York group that promotes philanthropy.

The Hsiehs say giving will always be at the core of how they live. But they might spend a little more than the median income if, for example, a family member needed help.

“It’s not a threshold of faithfulness or unfaithfulness,” says Mr. Hsieh of the income benchmark. But, he says, it’s been important to create some standard to hold themselves to: “It felt for us like a good check on reality.”