Before joining CBS-TV, Leider produced several plays in New York and London, among them Sir John Gielgud's one-man show The Ages of Man and The Visit starring Alfred Lunt and Lynn Fontanne.

During five years at Warners TV, he presided over numerous weekly television series, such as The FBI, Kung Fu, Wonder Woman, and Alice[1] and survived the wrath of short-time owner David Geffen.

After he "wrestled the story rights away from United Artists and Warner Bros.,"[3] Leider's first theatrical feature was a remake of The Jazz Singer with Laurence Olivier and Neil Diamond in the title role.

[1] From 1995 through 2009, He had produced several movies in partnership with Robert Shapiro including a feature version of the series My Favorite Martian,[6] Just Peck, and Confessions of a Teenage Drama Queen starring Lindsay Lohan.

[7] Leider has several motion pictures currently in pre-production or development including a new adaptation (following his 1994 HBO project[8]) of the Robert Harris’ novel Fatherland, Anne Frank and Me (from the novel by Cherie Bennett and Jeff Gottesfeld), Billy (from the novel by Albert French),[9] and The October Gang (by Kevin Clarke).