He was particularly known for his work on Kurt Weill, who he "almost single-handedly rescued [...] from neglect and promoted him to his present position as an important 20th-century composer".
He also produced performing editions of many of Weill's works and devised the significant celebration and revival of many of Weill's works at the 1975 Berliner Musikfest; much of this project was later recorded by the participating artists and the London Sinfonietta conducted by David Atherton and issued by the Decca Record Company in 1976.
Other composers he was known for advocating were the Pole Henryk Górecki,[6] Americans Elliott Carter and Roger Sessions, Germans and Austrians HK Gruber, Kurt Schwertsik, Berthold Goldschmidt, Leopold Spinner, Boris Blacher and Rudolf Wagner-Régeny, Italian Luigi Dallapiccola, Catalan exile Roberto Gerhard (a close friend from his student days in Cambridge), conductor-composer Igor Markevitch and British composers Alexander Goehr, Robin Holloway, Christopher Shaw and Walter Leigh.
In the 1960s and 1970s he devised, managed and edited an important series of recordings of 20th-century and contemporary music under the aegis of the Gulbenkian Foundation.
After his departure from Boosey & Hawkes, Drew worked in a similar capacity producing recordings for the German label Largo Records - these included a Weill album, 'Berlin im Licht', a series of recordings of music by Berthold Goldschmidt, and a double album including works by Weill, Blacher, Goldschmidt, Milhaud, Vaughan Williams and Harrington Shortall entitled Testimonies of War: Kriegzeugnisse 1914-45.