The American Composers Orchestra Looks Ahead George Manahan conducting the American Composers Orchestra as part of the Underwood New Music readings in 2010. WHEN economic waters are rough - or perhaps just to shake things up in times of stagnation - musical institutions try to redefine themselves, sharpen their sense of mission and do some image tweaking. That can be hard when your mission is already unusual and clearly defined. But the American Composers Orchestra, which has been putting a spotlight on (mostly contemporary) American music since 1977, has lately been reinventing itself as a hybrid performing ensemble and service organization. Mr. Manahan and the vocalist Joan La Barbara, performing in the Playing It UNsafe program in 2011. "I think of the A.C.O. a little bit like the Bronx Zoo," Michael Geller, the orchestra's executive director, said recently. "If you didn't know anything about zoos, and I asked you what its mission was, you would say, "It looks like a place where grandparents take children to entertain themselves while they're getting to observe living creatures." But of course their mission is not that. Their mission is environmental. It's about protecting species. It's about doing research. The zoo is the public face of it, and that's important. Clearly if it were just a research center, it wouldn't be the same. For us the concerts are the public face of what we do. But there really has to be some strategic, intellectual and artistic rigor in how we present that public face. I don't think anybody, from the start of the A.C.O., ever thought that presenting a good concert was the ultimate end. But whatever anyone may have thought, giving concerts was mostly what this polished freelance ensemble did for its first 15 years. It also commissioned new works. But it was not until the early 1990s that it began adding programs like the Underwood New Music Readings - free public sessions at which young composers hear their works rehearsed and recorded - and festivals like Sonidos de las Américas, which brought Latin American music into its purview. Today, on a modest budget of $1.75 million, the orchestra plays three or four concerts a season at Zankel Hall and offers special events, like the American premiere of Philip Glass's Ninth Symphony at Carnegie Hall in February. But now performances are a fraction of its activity. The Underwood readings offer a glimpse of what Mr. Geller sees as a more useful future for his organization. Originally they were held on a single day, with several conductors splitting the work. This year the readings are spread over three days: the first two, on Friday and Saturday at the DiMenna Center for Classical Music, are open to the public; the Sunday session is for the composers only. And George Manahan, the former music director of the New York City Opera who took over the American Composers Orchestra's podium in 2010, is doing all the conducting: a change, he said, that allows him greater flexibility in allotting time and resources for works of varying difficulty. As in past years, one of the six participating composers - Ryan Chase, Peter Fahey, Michael-Thomas Foumai, Paul Kerekes, Pin Hsin Lin and Benjamin Taylor - will win a $15,000 commission. Mr. Geller has also added an audience-choice award and workshops on copyright and intellectual property law, fund-raising, score engraving, self-publishing and publicity. Derek Bermel, who was the orchestra's composer in residence from 2006 to 2009 and is now its creative adviser - part of a team that oversees its programming, including Mr. Manahan and Robert Beaser, the artistic director - has benefited from the boost the readings can give a composer. In 1994, while he was still a student, his "Dust Dances," a work based on African xylophone music that he now describes as "my first presentable orchestra piece," was accepted for the readings. "I had no idea how a lot of what I wrote would sound," Mr. Bermel said in a telephone interview from Los Angeles, where he is composer in residence at the Los Angeles Chamber Orchestra. So while it was gratifying just to hear it, it also helped me assess, both in the moment and for a long time afterward, what I had done well and badly, what needed work, what was an interesting idea but might not have been clear. There were also frustrations. I had a 30-minute block, and that's a short time for an orchestra to absorb something. There was no chance to make corrections. It was just boom, and it was over. I remember feelings of exhilaration, frustration and embarrassment. It was overwhelming.