More than 50 museums in the central Puget Sound area will offer two-for-one admission deals or other special programs for eight days beginning Friday, in conjunction with an event drawing museum professionals from around the world.

The American Alliance of Museums, holding its annual meeting in Seattle for the first time in 20 years, is expected to attract 5,000 museum leaders from more than 50 countries.

Although the alliance’s event, based at the Washington State Convention Center Saturday through Wednesday, is not open to the public, area museums are using the opportunity to host the first Museum Week Northwest, (www.museumweeknw.com) with offers and events for the public.

For museum operators across the nation, “The biggest ongoing challenge we face is having people understand what museums do. We have everything from A to Z: art museums to zoos,” said Ford Bell, alliance president.

He said America’s 17,500 museums long ago outgrew the stereotype of just being places to house artifacts and hang documents on the wall. Instead, they offer an expanding array of educational, innovative and community-building projects.

Bell said the Institute of Museum and Library Services, a federal agency, found that annually U.S. museums draw some 850 million visitors — more than six times the combined attendance of four major pro sports: football, baseball, basketball and hockey.

As alliance president since 2007, Bell, who lives in Potomac, Md., has seen museums weather difficult times.

Although few major museums disappeared in the recession, many had to make painful cuts in staff, programs and projects, he said.

Now museums are expanding their activities. In Seattle, museum leaders will compare notes on everything from architecture to security, marketing to exhibit technology, robots to drones.

Bell said innovative museums in the Seattle-Tacoma area demonstrate an awareness that “Museums are economic drivers … an essential part of the tourism infrastructure.”

Among those he cited in Seattle were the Museum of History & Industry (MOHAI), the Museum of Flight and the Wing Luke Museum, and in Tacoma, the Museum of Glass and the Washington State History Museum.

Doug King, president/CEO of Seattle’s Museum of Flight, chairs the host committee for the gathering.

King said a combined 56 museums in the central Puget Sound area attract nearly 7 million visitors annually. In addition, he said, nearly 10,000 museum volunteers and employees host 1.34 million schoolchildren each year for visits and educational field trips.

Dan Leach, spokesman for The Center for Wooden Boats, said local museum officials intend to have Museum Week Northwest become an annual event.

Jack Broom: jbroom@seattletimes.com or 206-464-2222