Tomorrow evening, Musicians for Harmony, an organization founded shortly after the events of September 11, 2001, by violinist and arts administrator Allegra Klein, will hold its sixth annual memorial Concert for Peace. But in addition to commemorating the events of that day, this year’s concert will be a homecoming of sorts for Ms. Klein, who returned in late July from Iraq, where she also traveled in 2003 to deliver funds and instruments that Musicians for Harmony donated to the Iraq National Symphony Orchestra. This year, Ms. Klein was the sole New Yorker on the faculty of the National Unity Performing Arts Academy, a nine-day initiative organized by the nonprofit American Voices that held classes, workshops, and performances in the Kurdish city of Erbil under the direction of John Ferguson.

“John said to be prepared for anything,” Ms. Klein told The New York Sun, “so I had developed elementary programs and something advanced. The Erbil orchestra hadn’t been working in two or three years and didn’t have a conductor, so I stepped in,” she said. “The level of ability varied greatly. We worked on the Bach Air from the Suite in D major, and broke it down part by part, measure by measure. When they put it together and played it, the shock on their faces was amazing.”

Ms. Klein encountered her fair share of technical difficulties. Because the practice rooms had tile floors, the cello pins couldn’t grip the surface, and the instruments would slip out of the players’ control. The musicians, however, proved resourceful: The principal cellist fashioned rock stops out of his belt and suspenders.

Mr. Ferguson spoke with the Sun from the American Voices offices in Bangkok, where he was sorting T-shirts to send to academy participants back in Erbil. “We had close to 300 participants: 150 classical, about 40 jazz, 40 theater, with many between the ages of 8 and 16, with 60 dance students in ballet, hip-hop, and Broadway,” he said. “About 120 were brought up from the war zone of Baghdad.” Mr. Ferguson recalled a piano teacher from Baghdad, a Czech woman who’d married an Iraqi. “She hadn’t left her house in maybe three years because of the insurgency,” Mr. Ferguson said. While in Erbil, she practiced 14 hours a day, “because at home she has to take such care not to be heard and reported to Shia groups,” he said.

Ms. Klein’s approach of cultural diplomacy unites classical musicians with world musicians to expand the horizons of the players and the audiences, and this will be felt at tomorrow night’s concert, where the program will include the Shanghai Quartet, Baroque music, and two world premiers by Malian kora player Yacouba Sissoko. “It’s our first year at Symphony Space after five years at Merkin Hall,” Ms. Klein told the Sun. “We’re having classical musicians play chamber music and Baroque musicians play their music. Then Musique Sans Frontieres, which we founded with our artistic director Patrick Derivaz, has Western instrumentalists mixed with world musicians, for instance the pipa master Wu Man joined by violinst Colin Jacobsen with his brother, Eric, on cello for a premiere by Chinese composer Chen Yi.”

In addition to expanding the horizons of the classical audience, the Concert for Peace supports the varied projects of Musicians for Harmony, one of which is a music program in Crown Heights that unites Israeli and Arab students.