Beltrami's signature style is based around highly percussive texture. He often employs both traditional percussive instruments like bass drums, as well as violins and brass instruments, forming layers of hits and stabs.
Beltrami has worked repeatedly with such directors as Len Wiseman, John Moore, Wes Craven, and Guillermo del Toro. He has also worked with other musicians, including Marilyn Manson (for Resident Evil).
It was reported in October 2002 on Beltrami's official website that he had worked on orchestral arrangements for Thyme, The General and Leave Me Alone from the then-unreleased Guns N' Roses album Chinese Democracy. While none of those tracks appear on the final track listing of the album, they were confirmed as being recorded during the sessions with a possible chance of release in the future. However, he was credited officially for providing arrangements on Street Of Dreams, Madagascar, There Was A Time, This I Love and Prostitute. As a sidenote, 'Chinese Democracy' is also the name of a track on Beltrami's score for 3:10 to Yuma.