Performers of her work have included New York City Opera VOX, the London Sinfonietta, International Contemporary Ensemble, the Boston Symphony, the BBC National Orchestra of Wales, and the Tokyo Philharmonic.

In 2001, she was the first woman to win the Takemitsu Prize;[6] in 2007 she received a Charles Ives Fellowship from the American Academy of Arts and Letters[7] with a citation for music, "by turns, urgent, poetic, evocative and witty."

[16] Sierra's earlier works have their origins in military strategy and game theory, with literary sources including Vitruvius and Sun Tzu, notably: Ballistae (2000) for large ensemble and Surrounded Ground (2008) for sextet,[17] as well as Art of War (2010), a concerto for piano and orchestra.

[20] These two interests – nature and military strategy – are both evident in her 2009 orchestral work Game of Attrition which takes its structure from processes described by Charles Darwin in The Origin of Species.

[26] Since 2012, she has been working on a series of original scores to films by Maya Deren for a variety of chamber ensembles, including Meditation on Violence[27] and Ritual in Transfigured Time.