The first new Hilary Duff music to follow her hit debut album, "Metamorphosis," will be found on the soundtrack to her upcoming Warner Bros. Pictures film, "A Cinderella Story." Due July 13 from Hollywood Records, the set features four new songs by the singer/actress, including a duet with older sister Haylie Duff.

The soundtrack's lead single will be the Duff sisters' cover of the Go-Go's "Our Lips are Sealed." A video directed by Chris Applebaum, who did the same for Duff's "So Yesterday" clip, will debut June 3 on MTV.

Also included on the soundtrack are the new Duff songs "Crash World," "The Girl Can Rock" and "Now You Know," along with the "Metamorphosis" cut "Anywhere But Here."

Released in August 2003, Duff's "Metamorphosis" reached No. 1 on The Billboard 200 in its second week on the chart. Her first non-holiday studio album, it has sold 3.1 million copies in the United States, according to Nielsen SoundScan.

Haylie Duff also adds "One in This World" to the "Cinderella" set, which features two cuts by Jesse McCartney and previously released songs by Goo Goo Dolls, Jimmy Eat World and MxPx.

An update of the classic fairytale, "A Cinderella Story" is scheduled to open July 16 in U.S. theaters. The film also features Jennifer Coolidge, Chad Michael Murray and Regina King.

To promote the film, Hilary Duff will make a slew of media appearances, including a free July 15 performance in New York's Bryant Park for ABC's "Good Morning America." Also to be accommodated that week are appearances on NBC's "The Tonight Show With Jay Leno," the syndicated morning show "Live With Regis & Kelley" and MTV's "Total Request Live."

Duff has a handful of performances scheduled this month, beginning with KHTS San Diego's 93.3 Your Show on May 14 at the city's Coors Amphitheatre. A larger U.S. tour will kick off July 20 in Worcester, Mass.

Earlier this year, Duff wrapped shooting of the film "Heart of Summer" and has roles lined up in the features "The Perfect Man" and "Outward Blonde."

Here is the "A Cinderella Story" soundtrack list (not in final running order):

"Our Lips are Sealed," Hilary and Haylie Duff
"Crash World," Hilary Duff
"The Girl Can Rock," Hilary Duff
"Now You Know," Hilary Duff
"Anywhere But Here," Hilary Duff
"One in This World," Haylie Duff
"Beautiful Soul," Jesse McCartney
"Best Day of My Life," Jesse McCartney
"Sympathy," Goo Goo Dolls
"Hear You Me," Jimmy Eat World
"First Day of the Rest of Our Lives," MxPx

Here are Hilary Duff's tour dates:

May 14: Chula Vista, Calif. (Coors Amphitheatre)
May 15: Pasadena, Calif. (Rose Bowl)
May 16: West Hollywood, Calif. (House Of Blues)
July 20: Worcester, Mass. (Worcester's Centrum Centre)
July 21: Philadelphia (Wachovia Center)
July 22: Fairfax, Va. (Patriot Center)
July 24: Hershey, Pa. (Giant Center)
July 25: East Rutherford, N.J. (Continental Airlines Arena)
July 26: Uniondale, N.Y. (Nassau Coliseum)
July 27: Pittsburgh (Petersen Events Center)
July 29: Auburn Hills, Mich. (Palace Of Auburn Hills)
July 30: Rosemont, Ill. (Allstate Arena)
July 31: Milwaukee (Bradley Center)
Aug. 1: Minneapolis (Target Center)
Aug. 3: Saint Charles, Mo. (Family Arena)
Aug. 5: Nashville (Gaylord Entertainment Center)
Aug. 11: Jacksonville, Fla. (Jacksonville Veterans Memorial Arena)
Aug. 12: Tampa, Fla. (USF Sun Dome)
Aug. 13: Sunrise, Fla. (Office Depot Center)
Aug. 24: Oakland, Calif. (Oakland Arena)