Nissman's international career was personally launched by Eugene Ormandy with debuts arranged in all of the major European capitals[2] after he heard her perform as a student at the University of Michigan.

Nissman uncovered the manuscript of Ginastera's Concierto Argentino in the Fleisher Collection of the Free Library of Philadelphia and reintroduced the piece in 2011 with the blessings of the composer's estate.

[5] Nissman made history in 1989 by becoming the first pianist to perform the complete piano sonatas of Sergei Prokofiev in a series of three recitals in both New York and London.

"[8] In 1966 she was awarded a three-year National Defense Education Act Title IV fellowship for her master and doctoral studies at the University of Michigan.

Nissman was also awarded a three-year post-doctoral grant from the university (underwritten by the Power Foundation in 1969) to begin her international performing career.

[11] The profiled pianists, chosen from the thousands of past and present Steinway artists, also included Martha Argerich, Daniel Barenboim, Diana Krall, Van Cliburn, Billy Joel, Harry Connick Jr., James Levine, Murray Perahia, Edward Kennedy Ellington, Alfred Brendel, Randy Newman, Evgeny Kissin, Herbie Hancock, Krystian Zimerman, Christopher O'Riley, Maurizio Pollini, Ignace Jan Paderewski, Sergei Rachmaninoff, Marcus Roberts, Mitsuko Uchida, Richard Wagner, and Billy Taylor.

[12] In 2006, Nissman was elected to the Court of Honor of Distinguished Daughters of the Philadelphia High School for Girls "for outstanding lifetime achievement as an internationally acclaimed concert pianist, recording artist and educator."

28 (1961) in Geneva at his sixtieth birthday celebration, where she performed the work with L'Orchestre de la Suisse Romande conducted by Jean-Marie Auberson.

After Nissman discovered this concerto in the Edwin A. Fleisher Collection of Orchestral Music in Philadelphia, Aurora Natola-Ginastera, the widow of the composer, granted her exclusivity to perform the work and also to make available its first recording.

[24] In 2016 Nissman celebrated Ginastera's 100th birthday with a series of concerts devoted to the man and his music at Spectrum in NYC[25] and also at Kings Place, London[26] as well as master classes and lectures throughout the UK.

[32][33] As a Prokofiev scholar and authority, Nissman first visited the Soviet Union in 1984, at the height of the Cold War, as a guest of the Embassy of Denmark in Moscow.

Nissman was the first to perform and record Bartók’s unpublished 1898 Sonata, which she discovered in the Morgan Library's manuscript collection while researching her book.

"[45] This was the first time an international corporation employed a classical artist to appear in factories, plants, and branch houses throughout the United States, Mexico and Europe.

[51] Walter Cronkite hosted the event that also included appearances by Rosalyn Tureck, Paul Winter, Michael Tree, Zubin Mehta, and readings by the actor Gregory Peck and the poets Robert Penn Warren, Daniel Haberman and Edgar Bowers.

[53] For the 1996 Kennedy Center 25th Anniversary Gala Concert, broadcast on public television, Nissman performed two numbers arranged for ten pianos, alongside pianists Leonard Slatkin (who also conducted the ensemble), David Buechner, Cy Coleman, Joseph Kalichstein, Peter Nero, David Hyde Pierce, Peter Schickele, Jeffrey Siegel, and Alicia Witt.

[55][56][57] In November 2014 she performed at a gala at the de Young Museum in San Francisco to honor Dr. Arthur Ammann, founder of Global Strategies, an organization that serves the healthcare needs of women and children in neglected areas of the world.

Also heard as Liszt's contemporaries are Billy Joel (Chopin), Don Henley (Brahms), Harry Connick Jr. (Czerny), Rebecca De Mornay (Clara Schumann), Rosemary Harris (Princess Carolyne Wittgenstein), John Schuck (Wagner), Leonard Slatkin (Schumann), Peter Schickele (Berlioz), David Dubal (Heine), Manfred Honeck (Beethoven, Goethe), Barbara Feldon (George Sand), Stuart Margolin (Carl Lachmund), Bill McGlaughlin (Grieg, Richard Strauss), Miles Chapin (Hans von Bülow) and the voices of Anna Singer, Dennis Rooney, Pete Ballard, Kermit Medsker & Jon Cavendish.The second part focuses on Liszt's masterwork, the B minor Sonata with personal insights into performance and appreciation of this complex work.