Cook became resident leader of the orchestra at Paddy Harmon's Dreamland Ballroom in Chicago from 1922 to 1927, acting as conductor and musical director.

Among those who played in Cook's band were Freddie Keppard, Jimmie Noone, Johnny St. Cyr, Zutty Singleton, Joe Poston [de], Andrew Hilaire, and Luis Russell.

[2] After 1927 Cook's orchestra played in Chicago at the Municipal Pier and the White City Ballroom.

[2] On Broadway, he had a number of important orchestration credits, including The Hot Mikado (1939) and the first U.S. production of The Boy Friend in collaboration with Ted Royal in 1954.

[4] A proponent of ragtime, he also worked frequently with Eubie Blake, supplying the arrangements for the 1952 revival of Shuffle Along.