Diana Butler Bass knows all the gloomy statistics about declining mainline Protestant churches but believes in their future. She studies mainline churches that are thriving to see what sets them apart from those that are dying.

Her findings contradict some popular theories about church growth, and she is sharing them at a three-day conference at Pittsburgh Theological Seminary in East Liberty.

Successful congregations cultivate spiritual practices in daily life, promote tradition without using it as a fence to keep people out and offer a quest for wisdom, not pat answers, she said.

"When all three of those things are knit together, I call it the architecture of vitality," said Dr. Bass, currently senior fellow at the Cathedral College of the Episcopal Washington National Cathedral in Washington, D.C.

From 2002 to 2006 she studied congregations that were experiencing renewal in the Episcopal Church, Evangelical Lutheran Church in America, United Methodist Church, Presbyterian Church (USA), Disciples of Christ and United Church of Christ. They ranged from 35 to 3,500 members and covered all demographics and most would not describe themselves as evangelical.

Americans are looking for new ways to experience religious community. Thriving congregations have been able to change the way they do ministry to create those communities, she said. Those that keep offering conventional church programs from the 1950s wither and die.

Today's American's don't inherit faith, they choose it, she said. Her research suggests "that millions of people would choose mainline denominations if we gave them something worth choosing."

She has found no single formula for a successful mainline congregation. Music can be classical or contemporary as long as "people feel the presence of God in it and can participate in it," she said.

No matter what their worship style, thriving mainline churches are strong in basic practices of faith, renewal through tradition and helping people develop spiritual wisdom, she said.

Practices include obvious things like hospitality. But she was surprised to identify diversity as something that strong churches cultivated. Experts used to preach homogeneity as a key to church growth.

But her most successful congregations "created communities that were purposefully diverse. That included racial diversity, theological diversity, political diversity and diversity of life experience," she said.

During the divisive 2004 election, "these churches extolled the fact that they would not vote the same -- and yet their churches were not breaking apart."

Appropriation of church tradition can take surprising twists. One Lutheran congregation that wanted to "go deeper" in faith called a pastor who was steeped in the Catholic spirituality of St. Ignatius Loyola. He started a program based on a 30-day Ignatian retreat, stretching it over a year and requiring each participant to commit for a full year.

One participant told Dr. Bass, "We used to talk about God here. Now we talk to God."

Her findings contradicted a popular belief that people join churches to find easy answers. She quoted a young man at a growing mainline church who told her, "I wasn't looking for the answers. I was looking for a safe place to ask my questions."

"People are on a quest for meaning," she said. "Meaning is not the same thing as answers. They want to know how to navigate suffering. What about their vocation or job? They want to know how they can change the world."

The "Transforming Faith" conference continues today and tomorrow, starting at 9 a.m. Daily admission ranges from $10 for only the 9:30 a.m. keynote addresses to $35 for a full day plus meals. For more information call 412-362-5610, ext. 2196.