Seventh-day Adventist Church leaders and support staff at the denomination’s headquarters are gearing up for next year’s 60th General Conference Session, a 10-day global spiritual gathering and business meeting. Preparations for Session, which in recent decades has been held every five years, invariably involve fielding a frequently asked question:

“Why does it seem like Session is always held in the United States?”

The short answer: because it usually is.

The longer answer involves numerous factors in selecting a Session site.

Indeed, the 2015 Session will be held in the United States. Nearly 2,600 voting delegates and tens of thousands of visitors are scheduled to meet in San Antonio in the state of Texas. And it’s true, Session has been held outside of the U.S. only three times: Vienna, Austria in 1975; Utrecht, Netherlands in 1995; and Toronto, Canada in 2000.

GC Session is one of the world’s largest religious events, and city tourism officials must make their pitch more than a decade in advance. The final selection is made by the denomination’s Executive Committee, which is comprised of 330 of church leaders from around the world.

In an interview, Session Manager George Egwakhe, who is an associate treasurer for the Adventist world church, shared the Executive Committee’s requirements for choosing a Session host site. (Insider tip: #2 is the main reason Session is usually held in the U.S.)

1. Indoor seating for 70,000 people. Nearly 2,600 delegates discuss and vote on policy items during business meetings each morning and afternoon. But in the evenings, crowds swell as two or three of the 13 world divisions each take a turn presenting the results of mission outreach in their territory over the past five years. Session is now usually held in a football or baseball stadium. The venue usually fills to near capacity on both Saturdays of Session for Sabbath worship. Now and then there is talk of scaling down the size of Session—which could open up the possibility of Session being held in a greater variety of countries—but that isn’t likely to happen soon. The 2020 Session is already set for Lucas Oil Stadium in Indianapolis, Indiana, United States.

2. An adjacent convention center. This requirement alone severely limits the number of potential host city sites around the world. While many prominent cities have an adequate indoor stadium, very few have a nearby convention hall. “Even in the United States we have a limited number of cities that can accommodate our needs because of this requirement,” Egwakhe says. In addition to business meetings, Session is also a global spiritual gathering and ministry trade show. Denominational and supporting ministry organizations set up booths in the convention center, and it becomes a place to network and check out new resources. Throughout the day, thousands of visitors view innovative ministries, products and new uses of technology for mission. They often help the Adventist Church’s mission in their own corner of the globe by taking home new ideas for ministry and spreading the gospel.

3. Accommodations. Session delegates need affordable hotels near the Session venue. With 10 straight days of all-day meetings, jet-lagged delegates and visitors can’t afford to travel across the city or from another town each morning and evening to conduct their work.

4. Air travel costs. “Flights to the United States are relatively less expensive than for most delegates to travel from their region to another part of the world,” Egwakhe says. Europe could be a viable travel option, but again, it doesn’t have a city that meets requirement #2. Also, most Session support staff are based in the U.S., which saves on overall travel costs for a large block of attendees.

5. English-speaking venue staff. English is the official business language of the Adventist world church. Therefore, stadium support staff must be able to converse with Adventist leaders on a myriad of issues—everything from “We’d like to receive a bid from your venue to hold Session” to “Excuse me, where is the information desk?”

6. Visas. According to this year’s 2014 Statistical Report, the Adventist Church operates in 215 countries. With such a diverse world family meeting together, it’s important to hold the gathering in a country that is accessible to as many people as possible. “The United States is very open in granting visitor visas to a lot of people in the world,” Egwakhe says.

For more information about the 2015 GC Session, visit the website 2015.gcsession.org