With more Americans working overseas, especially in Asia, leaders connected with foreign churches want mission boards and others stateside to devote more resources to their thriving congregations, in order to serve the needs of expatriate Christians.

"The world has become such a global village, and that necessitates all mission bodies to rethink their philosophy of international church ministries," says Louella Gould, who is director of women's ministries at the Evangelical Church of Bangkok where her husband, Bob, is the senior pastor.

"For many church and mission-sending bodies, focusing on this group is not at the top of the list of priorities," she says. For example, Gould says, there are at least 350,000 English-speaking expatriates in Bangkok. "This group has be come a tremendous opportunity for ministry and evangelism."

TEMPORARY ASSIGNMENT: Stretching from Islamabad to Istanbul, Ecuador to Estonia, nearly 600 overseas English-language churches exist for expatriates.

"The main distinctive of an overseas church is that many of the members are transients," says David Chism, pastor of Mexico City's Capital City Baptist Church. "They know when they arrive that they will be in the city for a short period."

Pastor Dave Petrescue of the Maadi Community Church in Cairo agrees. "There is a distinct sense of the temporary. We are sojourners."

International congregations often appear to be a mini–United Nations. Petrescue says his congregation counts members from 32 nationalities and 50 denominations. "To serve the diverse expatriate population well, the church must be broad enough to include people from various cultures and denominations without losing its focus and doctrinal base," Petrescue says.

Despite the diversity, most pastors ...