1990s: Under Cover

In the 1990s, Manilow's album career changed significantly. His recordings switched from him being primarily a singer-songwriter to him being a cover artist. A trend that started with the 1989 release Barry Manilow, continued with his 1990 Christmas LP Because It's Christmas. Consequent event albums followed including: Showstoppers, a collection of Broadway songs (1991), Singin' with the Big Bands (1994) and a late 1970s collection Summer of '78 (1996) which included the hit I Go Crazy, formerly a hit for Paul Davis in 1978. Many consider this to be the weakest effort of Manilow's career. The decade ended with Manilow recording a tribute to Frank Sinatra Manilow Sings Sinatra (1998) released months after Sinatra's death.

In 1990, Japan aired National Eolia Special: Barry Manilow On Broadway where he sang the title song Eolia, which was used as a song there in a commercial for an air conditioner company of the same name, as well as other songs from his 1989–1990 Live on Broadway tour.

In the early 1990s, Manilow signed on with Don Bluth to compose the songs with lyricists Jack Feldman and Bruce Sussman for three animated films. He co-wrote the Broadway-style musical scores for Thumbelina (1994) and The Pebble and the Penguin (1995). The third film, entitled Rapunzel, was shelved after the poor performance of Pebble. Manilow was also to be cast as the voice of a cricket. Manilow also composed the score and wrote two songs with Bruce Sussman for Disney Sing Along Songs: Let's Go To The Circus. But unfortunately, because of a contract agreed by both of them, Andrew Belling and Domenick Allen were credited as composers, meaning that nobody isn't supposed to know that a celebrity like Manilow should be credited in that movie.

On February 19, 1992, Manilow testified before the Subcommittee on Intellectual Property and Judicial Administration House Committee in support of H.R. 3204 The Audio Home Recording Act of 1991. The bill was signed into law on October 28, 1992 by President George H. W. Bush. The Act, an historic compromise between the consumer electronics and music industries, became effective immediately.

In 1993, PBS aired Barry Manilow: The Best of Me, taped at Wembley Arena in England that year, to fundraise. The BBC also played a one-hour version of the same show including The Best of Me sung during the concert, a bonus song or lucky strike extra as Manilow says, not seen in The Greatest Hits...and then some, the video release of the show; however, the song was included on the DVD of the same title, with Manilow seated in front of a black curtain, lip-syncing to the recording.

Manilow branched out in another direction and with longtime lyricist Bruce Sussman launched Copacabana, a musical play based on previous Manilow-related adaptations. They wrote new songs and it ran for two years on the London West End and a tour company formed.

In December 1996, A&E aired Barry Manilow: Live By Request, the first of two Live By Requests he does. The broadcast was A&E's most successful music program, attracting an estimated 2.4 million viewers. The show was also simulcast on the radio. In March 1997, VH-1 aired Barry Manilow: The Summer of '78, a one-hour special of Manilow solo at the piano being interviewed and playing his greatest hits as well as songs from Summer of '78 his latest release at the time.

In another collaboration between Manilow and Sussman they co-wrote the musical Harmony, which previewed October 7 to November 23, 1997 at the La Jolla Playhouse in La Jolla, California. Later in 2003, Harmony was originally scheduled for a tryout run in Philadelphia before going to Broadway, but was cancelled after financial difficulties. After a legal battle with Mark Schwartz, the show's producer, Manilow and Sussman in 2005 won back the rights to the musical. It is currently unknown when the musical will reach Broadway.

On October 23, 1999, NBC aired the two-hour special StarSkates Salute to Barry Manilow taped at the Mandalay Bay Hotel in Las Vegas, Nevada featuring numerous figure skaters performing to Manilow's music. Manilow also performed as well.