Michael E. Shapiro, the crowd-pleasing director who presided over two decades of explosive growth at the High Museum, announced Wednesday he would be stepping down.

“I think, after 20 years, why not give someone else a shot to take it to the next level?” said Shapiro, in an exclusive interview with The Atlanta Journal-Constitution.

Shapiro will leave the High July 31, 2015, as he completes his 20th year guiding the museum, first as deputy director, then as director.

It has been a time of momentous change at the Midtown cultural center.

During Shapiro’s tenure the High constructed a three-building expansion designed by Italian architect Renzo Piano, more than doubling the facility’s footprint.

The museum also stepped up its acquisitions, almost doubling its permanent collection, and adding the works of some artists, including Ellsworth Kelly and Alex Katz, by the roomful.

But Shapiro’s most notable influence was in the High’s collaborations with museums in Europe and Asia, through which he organized exhibitions of blockbuster traveling shows, some featuring works never before seen in the U.S.

The most ambitious of these was the High’s ongoing relationship with the Louvre which brought nearly 500 works of art from Paris to Atlanta between 2006 and 2009. The first year of the “Louvre Atlanta” partnership attracted 397,000 visitors to the museum, the second-highest attendance of any show.

Of those exchanges, Shapiro said, “it was just a relentless march of great visual treats.”