In March 2012, Universal Edition Vienna announced the publication of Helder’s orchestration of Mahler’s Piano Quartet, commissioned by the Rotterdam Philharmonic Orchestra. It will be premiered in May 2013 by the RPhO and conductor James Gaffigan. The Asian premiere will be held in August 2013 with the Seoul Philharmonic. She is commissioned by the re:orchestra to write her first double concerto for violin and bassoon which will also be premiered in May 2013.

Helder has performed with several Dutch and German orchestras and toured in Russia, the USA, Mexico and Europe. Her works are frequently performed in cities around the world.
Her concerts include a wide range of repertoire, including chamber music for voice and piano, violin and piano, cello and piano, piano trio and piano quartet. She feels especially close to the music of Beethoven, Schubert and Debussy as well as 20th century compositions. Next season will include a Schubert recital tour.