The American Press Institute building in Reston, Va. (Jahi Chikwendiu/Washington Post)

In a sign of the times for the troubled newspaper industry, the nation’s most venerable press-management and training organization will lay off its staff and shutter its landmark headquarters on Friday.

The American Press Institute of Reston will cease independent operations after 66 years and combine with a unit of the newspaper industry’s main trade group, the Arlington-based Newspaper Association of America, under a merger approved by the two organizations’ boards in January.

As a result, API will vacate its distinctive headquarters, a modernist building designed by noted Bauhaus architect Marcel Breuer, and it has dismissed its eight full-time employees and one part-timer.

Its assets — primarily a multimillion-dollar endowment — will be pooled with the NAA Foundation’s endowment to fund programs, said Bob Weil, API’s vice chairman and an executive with McClatchy, the Sacramento-based newspaper company.

API gave seminars, conferences and workshops for thousands of media executives and journalists from around the world. It was founded in 1946 by Sevellon Brown, the late editor and publisher of the Providence Journal, and originally was housed at Columbia University in New York.

At its peak in the 1990s, the nonprofit organization employed more than 30 people to run its frequent programs.

But API’s fortunes declined in parallel with those of newspapers, which were once one of the most profitable businesses in the nation. The combination of shifting reading habits, the onset of digital competition, consolidation of chain-store advertisers and the recession pared industry revenue by 44 percent between 2001 and 2011, according to the Newspaper Association. This has pushed several major chains into bankruptcy and triggered widespread cutbacks in newsrooms.

The decline has forced newspapers — the main supporters of API — to trim their contributions to the organization. At the same time, news organizations have reduced the number of people who attend API-produced programs, said Caroline Little, the chief executive of NAA.

“People don’t have the time or means to travel,” she said. “The budgets aren’t there to send people to Reston for a week.”

As a result, API has been losing “substantial amounts of money,” Little said. “The older model of API wasn’t working and hasn’t for a while.”

Weil said API could have survived another five to 10 years based on the rate it was spending its endowment, whose value he declined to disclose. He said, however, “there was a clear sense we needed to do something different. The media landscape has changed significantly.”

A merger made sense, he said, because media companies were already contributing to both API and the NAA Foundation. Added Weil, “API isn’t going away— it’s getting revitalized.”

API employees declined to speak for the record, citing terms of their severance agreements.

A new board is reviewing plans to continue some of API’s programs, but no initiatives have been announced.

The organization also hasn’t determined what to do with API’s building, Little and Weil said.