Julie Burros, who as Boston’s chief of arts and culture oversaw the formation of the city’s first cultural plan, is leaving city government for the private sector, she said Thursday.

Her last day as a city employee is June 29. Kara Elliott-Ortega, who now serves as director of planning and policy in the office of arts and culture, will serve on an interim basis until a replacement is found.

“I feel like I’ve gotten a ton done, and I’m ready for a new creative challenge,’’ said Burros, who will be heading up a national cultural planning practice at Metris Arts Consulting, based in Easton, Pa. “It felt like a decent time to make a transition, so the stars kind of aligned.’’

Burros, who in late 2014 became the city’s first arts czar in more than 20 years, a Cabinet-level position, oversaw the mayor’s Office of Arts and Culture, the Boston Art Commission, the Boston Cultural Council, and the Strand Theatre.

Her signature achievement, however, was the formation of Boston Creates, a sweeping cultural plan that serves as a creative road map for the city. The plan, which is meant to be implemented over the next decade, includes an effort to provide affordable housing for artists, a pilot program to provide rehearsal spaces for performers, and a percent-for-art program, which ties public art funding to new city capital projects.

“This is the largest municipal investment in the arts,’’ said Burros. “It’s going to remake how we do civic planning.’’

During her 3½-year tenure, ⅜Burros also oversaw the establishment of the city’s artist-in-residence program, the distribution of a variety of grants, and the creation of a resource desk to help artists navigate City Hall and find new opportunities.

Some Boston arts leaders were underwhelmed by a draft version of the cultural plan, calling for more sustainable revenue streams for the arts. But Walsh continued to support Burros. And the final plan included more than a million dollars in new arts funding.

“I am proud of the significant strides we’ve made in establishing Boston as a municipal arts leader, and bringing the arts closer to the heart of all we do,’’ Walsh said in a written statement. “I wish Julie the best in her future endeavors, and look forward to continuing our important work to support this growing sector of our economy.’’

Burros said she was gratified by the proliferation of public arts projects in Boston since her arrival.

She added, however, that there was still a lot of room for improvement before Boston is truly hospitable to the arts and to artists.

“I think space is really the biggest issue,’’ she said. “There are a number of cultural spaces that have been secured . . . and more spaces are coming on line, but there’s still work to be done.’’

Malcolm Gay can be reached at malcolm.gay@globe.com. Follow him on Twitter at @malcolmgay.