During a long hiatus between albums back in the mid-80s, Def Leppard feared metal/pop crossover groups such as Bon Jovi had hijacked its core audience. In 2000, Bon Jovi returned to the airwaves with

During a long hiatus between albums back in the mid-80s, Def Leppard feared metal/pop crossover groups such as Bon Jovi had hijacked its core audience. In 2000, Bon Jovi returned to the airwaves with full force thanks to the single "It's My Life," a crossover Phil Collen and his bandmates are hoping to duplicate with their new Island album, "X."

"The rules have completely changed," he tells Billboard.com. "The reason Bon Jovi is having success now is they have a great image and it is appealing to a lot of younger people. It's crossing over to pop music basically. 'Hysteria' was that, crossing over to pop."

It's been 15 years since the release of "Hysteria," which has sold 17 million copies to date, according to the label. Interest in Def Leppard's catalog remains high, with the album "Vault -- Greatest Hits 1980 - 1995" having spent 296 weeks on Billboard's Pop Catalog Albums chart. Response to "X," which debuted at No. 11 on The Billboard 200 in August, has been fairly positive, with most critics citing the band's return to quintessential Def Leppard riffs and hooks. But Collen assures that any similarities construed as aping past glories is purely happenstance.

"On [1999's] 'Euphoria' we desperately tried to do that," he says with a laugh. "With 'Promises,' I made the riff in the same key as 'Armageddon It' and 'Photograph.' It's basically a rip-off. If another band was to do that to us, we'd go 'Jesus Christ, let's sue them.' But no one noticed. And on this record, we didn't do that at all. This record was quite liberating. We weren't sticking to any rigid walls or boundaries, which were done on pretty much all of the other records."

As for touring, Def Leppard is planning a trip to Japan this fall followed by a handful of Stateside shows before the end of the year. Early 2003 will include a jaunt through Europe, which will coincide with the release of a new single/video "Long Long Way To Go." A larger North American tour will likely begin next spring.

"We actually want to do some new stuff and some songs we haven't done because we've gotten into this little thing of playing the greatest hits, and everyone loves to hear it, but we're kind of a bit sick of playing it," says Collen. "It's very hard. You have to really mix it up. 'Billy's Got a Gun' or 'White Lightning' or songs like that could resurface. We're just trying to figure out the songs that are going to work live."