San Francisco native and composer Lisa Bielawa has taken site-specific performance to another level. The arias in her collaboration with the world-renowned soprano Susan Narucki, Chance Encounter, were written from snippets of conversation overheard in public. The entrance times of the musicians are changed to reflect each location the piece is performed in, and the whole thing unfolds like a well-planned flash-mob. Her Airfield Broadcasts project is similarly large-scale and ambitious. The Tempelhof Broadcast brought a full orchestra to a former airstrip famous for its role in the Berlin airlift of the late '40s, and the Crissy Broadcast in San Francisco will feature more than 800 musicians in a free orchestral concert on Crissy Field. At a time when the news has been full of BART strikes and government shutdown, Bielawa hopes her concert reminds everyone how beneficial public space can be. "I would like to see this project bring about new partnerships, new vitality, and new relationships between arts and civic institutions, between different generations and economic strata, between arts or music lovers and totally non-arts-identified parkgoers," she says.