Parton's work with Wagoner was hugely popular with audiences, but after the fact, listening to their recordings together (you can find a representative sampling on RCA's "The Essential Porter Wagoner and Dolly Parton"), you can hear how Parton stays well within the margins of the material. Wagoner's voice, while pleasant enough, had limitations; Parton's seemed as if it was aching to soar.

In 1974, feeling constrained by her professional partnership with Wagoner, she left his show, and the breakup was bitter. Several years later, Wagoner sued Parton over certain contractual obligations, making the rift between the two even deeper. In her book and elsewhere, Parton has freely admitted that she wrote her 1974 hit "I Will Always Love You" as an elegy for her broken relationship with Wagoner, a relationship that was always platonic, but at times stormily passionate. (Parton has always been amusingly wry about the rumors of her romantic liaison with Wagoner. When Tammy Wynette, who'd also sung with Wagoner, fretted that Wagoner might claim he'd slept with her, as he had about most of his other singing partners, Parton quipped, "Don't worry, Tammy, half of the people will think he's lying and the other half will just think we had bad taste.")

Parton's country career flourished in the '70s, and she briefly had her own TV show in the mid-'70s (as well as a second series in the late '80s). The earlier part of the '70s was undoubtedly the golden age of her own songwriting, the era of "Coat of Many Colors," "Jolene" and countless others. But she had her sights set on being more than a country star: Her great ambition was to crack the pop Top 40, to make hits that would be embraced by more than just her loyal country audience. In late 1977 she got her wish, when "Here You Come Again" hit No. 3 on the Billboard charts.

Parton takes credit (some of us would prefer to call it blame) for laying the groundwork for the country boom of the 1990s, a period when country suddenly chomped down on a huge segment of the pop-music market. But she's also acutely aware of how that boom ultimately hurt her. The country-music machine of the past decade -- and the country recording industry has been nothing if not a machine, cranking out "stars" whose prefab country is mostly an insult to the genre -- had little use for "old-timers" like Parton. She and her peers (among them luminaries like George Jones, Johnny Cash and Merle Haggard, the latter two of whom found respect in their later careers only in the rock recording world) were shut out of country radio in favor of singers who were allegedly more modern. "The 'normalization' of country music and the Top-40 kind of thinking that goes with it have made it hard for an over-40 hillbilly to get radio airplay anymore," she noted ruefully in her book, adding, "Hey, DJs, I'm forever 39, so please play my records!" In 1996 Parton closed her Nashville office; in 1997 she dissolved her loyal fan club. She seemed to be distancing herself not so much from country music itself as from the monster it had become, and who could blame her?

But Parton has never complained about her mainstream success. Actually, she's milked it. Parton's sweet, sexy demeanor (not to mention her boldness in showing off her bodaciously rounded figure) shouldn't fool anyone into thinking she's anything but an intense and incredibly smart businesswoman. Her Tennessee theme park, Dollywood, is a popular tourist attraction. And although her movies, with the exception of the 1980 "9 to 5," haven't been huge hits, you can't blame her for trying to translate her particular brand of sparkle to the big screen. "9 to 5" is nothing more than an inane revenge fantasy masquerading as a feminist statement, but Parton stands apart from her costars Lily Tomlin and Jane Fonda as the movie's most memorable personality. She's a charmer, and her speaking voice alone is gently musical. But there's also a no-nonsense crispness about her (particularly in a scene where she goes to the trunk of a car to get a crowbar and calmly assesses the dead body that's stashed there). That seems to be a real-life trait, a characteristic that helps her get things done, rather than just hanging around dreaming about them.

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