Denes Agay (1911-2007) was a Hungarian-born American composer, arranger and author. Agay was born and raised in a small village near Budapest and began playing piano at the age of three. In 1934 he completed his musical studies at the Franz Liszt Academy in Budapest.

Agay conducted the Budapest Philharmonic Orchestra in a performance of a symphony which he composed. He worked as a film composer; one film assignment was writing the background music for Hedy Lamarr's nude scene in the 1933 film Ecstasy. Agay was a Jew, and after the rise of Nazism, he emigrated to New York in 1939. In 1942 he became an American citizen and joined the military, entertaining patients in the hospital wards. His parents died in Auschwitz. After the Second World War Agay worked as a teacher, composer and publisher, and as a conductor and arranger on the NBC show Guest Star. He wrote more than 90 books about musical subjects, including a multi-volume collection of piano arrangements, The Young Pianist's Library, and in 1975 produced the popular anthology, Best Loved Songs of the American People. Agay also continued to compose. His lively Sonatina no. 3 was frequently performed by young performers at piano recitals.

Agay and his wife endowed the Denes and Mary Agay Piano and Composition Scholarship Fund at the Peabody Conservatory. He died in Los Altos, California in 2007 at the age of 95.