Born to a Jewish family[1] in Chicago to Ester Huff and William Masser,[2][3] he attended the University of Illinois College of Law.

[4] Masser's first major composition hit, co-written with Ron Miller, was "Touch Me in the Morning", recorded by Diana Ross.

His hit songs by other artists include "Hold Me" (Teddy Pendergrass and Whitney Houston), "Tonight, I Celebrate My Love" (Roberta Flack and Peabo Bryson), "If Ever You're in My Arms Again" (Peabo Bryson), "Miss You Like Crazy" (Natalie Cole) and "Someone That I Used To Love" (Natalie Cole), "So Sad the Song" (Teddy Pendergrass, Gladys Knight), and "It's My Turn" and "Last Time I Saw Him" (Diana Ross).

Masser was nominated for an Academy Award in 1976 for Best Music, Original Song, for "Theme from Mahogany (Do You Know Where You're Going To)," which he wrote with Gerry Goffin.

Among the many recordings that Masser produced are Barbra Streisand's "Someone That I Used to Love" (originally a hit for Natalie Cole) and the duet by Judy Collins and T. G. Sheppard, "Home Again".