Krens Steps Down as Guggenheim Director

The foundation said that Mr. Krens would remain as director until a successor was hired, and that the search would begin immediately. But it added that the institution would revert to the management structure that existed until 2005, appointing a director who would run the Manhattan flagship and Guggenheim satellites.

In September 2005 the foundation promoted Lisa Dennison, then a deputy director and chief curator, to director of the Manhattan museum. She served less than two years, departing last summer to join Sotheby’s auction house as an executive. Curators and other museum directors have been saying privately for months that the Guggenheim has been unable to fill the crucial job of director of the New York museum. They said that candidates who were informally approached were not shy about communicating that they would not work under Mr. Krens, who is known as a difficult personality.

Supporters of Mr. Krens, however, say he has been disappointed with the foundation’s board, especially its shortage of particularly generous donors. With no replacement for someone like Mr. Lewis, who gave the Guggenheim about $77 million overall — nearly four times as much as any other board member in its history — the Guggenheim may not have the financial muscle to keep growing, some art-world insiders say.

Mr. Krens cast his job change in a positive light on Wednesday. “This is a great move for everyone,” he said in a telephone interview after stepping off a flight from Paris to New York. “In July I will have been at the Guggenheim for 20 years, and I like that round number.”