What the U.S. women's soccer team did for female athletes this summer, Sarah McLachlan did for female musicians three years ago when she concocted the Lilith Fair as a celebration of women in music. Conventional wisdom in the concert industry held that having even two women on the same bill was not good business. McLachlan proved that having many--in fact, nothing but--women on the same bill was, in fact, great business, and the Lilith Fair quickly became a phenomenon, outpacing such testosterone-fueled ventures as Lollapalooza.

At Merriweather Post Pavilion Wednesday, the third and final Lilith Fair (McLachlan herself has pulled the plug) drew a full house, three-quarters of it women. As at previous fairs, the mood was celebratory around the crafts-and-causes village and second stages, and even the storm clouds that burst just as main-stage programming began did nothing to dampen soaring spirits.

After eight hours of music, the concert ended with McLachlan, Sheryl Crow, the Dixie Chicks and others gathered onstage for a wonderfully sloppy but engagingly spirited reading of Jackie DeShannon's 1969 hit "Put a Little Love in Your Heart."

Washington-born Me'Shell NdegeOcello opened the program with a too-short set drawn almost exclusively from her upcoming album, "Bitter." It's not due for another month, so NdegeOcello was performing material totally unfamiliar to the audience just at the moment the skies opened up--hardly the best circumstance for such a risky venture.

The new songs seemed evenly split between the '70s-style funk fusion of "Satisfy" and "Free My Mind" and airier meditations like "Faithful" and "Loyalty." NdegeOcello is moving toward a more introspective sound, but the bassist and her five-piece band were quick to settle into supple funk vamps.

The Mediaeval Baebes, a second-stage act elevated to the main stage because of thunderstorms, were an impressive sight--11, well, uh, Baebes clad in beautiful white dresses, delivering period songs accompanied by tin whistles, flutes, hurdy-gurdy and a pair of pagan percussionists. The British vocal ensemble simply went on too long, its ancient songs sounding all too similar all too quickly.

Leave it to a Middle Age performer--Chrissie Hynde--to rekindle the fire. At 48, Hynde is an unrepentant rocker who performs with the same fervent passion she did when she was starting out 20 years ago. Though Hynde and her band, the Pretenders, performed several songs from their new album, they drew mostly from their early-'80s songbook with such muscular, melodic classics as "Message of Love," a cascading "Talk of the Town," "My City Was Gone," "Don't Get Me Wrong" and the flat-out burner of a closer, "Middle of the Road." The evening's sweetest surprise arrived when Emmylou Harris came out for a luminous duet on "Hymn to Her," trading verses with Hynde and reaching deep into that song's compassionate heart. Harris later did cameos with Sheryl Crow (Gram Parsons's "Juanita") and McLachlan (the fragile "Angel").

Country music made its presence felt with the Dixie Chicks, one of the genre's hottest acts and one of its most gregarious. That's mostly thanks to lead singer Natalie Maines, whose spitfire energy and punkish abandon are a perfect foil to the vocal harmonies and instrumental prowess of fiddler Martie Seidel and banjo and dobro player Emily Robison.

The trio mixed material from its quadruple-platinum major-label debut--including the anthemic "Wide Open Spaces," the romantic laments "Tonight the Heartache's on Me" and "You Were Mine" and the resilient "I Can Love You Better"--with songs from its much-anticipated follow-up, due Aug. 29. These included the bouncy "Ready to Run," the divorce ditty "Sin Wagon" and "Goodbye Earl," a caustic abused-wife revenge anthem. The Dixie Chicks also turned in a hard-driving cover of Bonnie Raitt's blues-rocker "Give It Up or Let Me Go."

Crow's subsequent set seemed a bit sluggish, particularly when she unwisely thickened arrangements on such standards as "Leaving Las Vegas" and "Every Day Is a Winding Road." She did much better by bittersweet love ballads like the wistful "My Favorite Mistake" and the cello-and-violin-driven "Difficult Kind," and on such yearning complaints as "Anything but Down" and "If It Makes You Happy." Crow closed out her show with the Stones-style swagger of "There Goes the Neighborhood."

The energy level necessarily diminished when headliner McLachlan finally took to the stage at night's end. By nature, her music is more subtle and introspective, better suited to chamber-pop arrangements like those surrounding "I Will Remember You," "Adia," "Hold On" and the super-spare finale, "Angel." Even when she upped the energy level--on the sly "Ice Cream" and the keening "Sweet Surrender"--McLachlan sang with cool efficiency. Ultimately, her triumph can't be measured merely in terms of performance, but in the astounding accomplishment of the Lilith Fair as well. On both counts, McLachlan earned her standing ovations.