The quintessential arena-rock producer, Robert John "Mutt" Lange rose to fame on the strength of blockbuster albums from acts including Def Leppard, AC/DC and Foreigner. His career began in 1976, when he produced Graham Parker's Heat Treatment as well as the self-titled debut from City Boy, the first in a series of collaborations with the group. Lange's breakthrough followed three years later with AC/DC's seminal Highway to Hell. He reunited with the group a year later for the classic Back in Black, followed in 1981 by Foreigner's mega-hit 4, which earned him a Grammy nomination as Producer of the Year. That same year, he also helmed Def Leppard's High 'n' Dry, his first collaboration with the band; 1983's Pyromania made them stars, with Lange co-writing smash hits including "Photograph" and "Rock of Ages." Other hits he authored from the same period included Loverboy's "Lovin' Every Minute of It" and Huey Lewis & the News' "Do You Believe in Love."

After his next monster hit, the Cars' 1984 album Heartbeat City, Lange reunited with AC/DC on 1986's Who Made Who before returning to the Def Leppard camp for 1987's Hysteria, one of the best-selling rock albums of all time. With Billy Ocean's Tear Down These Walls, Lange moved into R&B, scoring a smash single with "Get Outta My Dreams, Get Into My Car." A long layoff preceded the release of his next production, Bryan Adams' 1991 LP Waking Up the Neighbours, which generated the mega-hit &"Everything I Do) I Do It for You". He then hit a snag with Def Leppard's disappointing 1992 effort Adrenalize, before returning to hitmaking form a year later with Michael Bolton's The One Thing While his skill as a producer and collaborator had by this point been proven many times over, Lange's next project would bring him still still greater success, and in some ways solidify his legacy. After the appearance of her 1993 debut, the producer met and fell in love with Shania Twain. The couple married, and soon after began work on Twain's follow-up. 1995's Woman in Me was an immediate hit, spawning the inescapable radio singles "Whose Bed Have Your Boots Been Under." and "Any Man of Mine". More importantly, it began to transform Twain's sound from polite contemporary country into straightforward pop with country overtones. The molting process was completed two years later with Come On Over. Buoyed by the AOR production and pop-influenced co-writing of Lange, Twain emerged as true superstar, with only a superficial association to country music. Plenty of Nashville songbirds followed the Lange/Twain team's lead, kicking the mud off their high heels to embrace the mainstream with gusto. In 1999, Lange moved back into pop with the Backstreet Boys hit Millennium; that same year he helmed Celine Dion's All the Way: A Decade of Song. The international versions of Britney Spears' Oops!...I Did It Again followed. Lange's magic touch struck again in 2001with the Corrs' In Blue; he produced the album and co-wrote "Breathless", its effortlessly sugary hit single. In November 2002 he and his wife reunited for Up! The album was initially released in three versions, mix tweaked alternately for pop, country, and international audiences. The move was derided by some , but it only proved Lange's prowess as a pop producer without need for genre qualification. ~ Jason Ankeny & Johnny Loftus, All Music Guide