Global Citizen Festival, With Neil Young, to Combat Poverty Cranked-up guitars and sobering statistics shared a Central Park audience of more than 60,000 people on Saturday at the Global Citizen Festival, a five-hour concert on the Great Lawn devoted to ending extreme poverty worldwide. The concert was also webcast internationally. The headliner was Neil Young with Crazy Horse, the band that has perfected rock as a primordial stomp. Sharing the lineup were guitar-driven bands that have obviously listened closely to Mr. Young through the years: Foo Fighters, the Black Keys and Band of Horses. It was a narrow, old-school, all-male slice of rock, with a hint of internationalism for starters: the rapper and singer K'Naan, who was born in Somalia and now lives in Canada (and whose band included a female keyboardist). An unannounced guest, John Legend, sang John Lennon's vision of global citizenship, "Imagine." Mr. Young's set was molten and unkempt, yet it had his own kind of finesse. He and Crazy Horse, on their first tour since 2004, often huddled near the center of the stage, bobbing back and forth until their heads nearly touched, and their songs sometimes welled up out of a caldron of drone and distortion. But Mr. Young's voice was pure and precise, and his lead guitar could peal with straightforward melodies, or scrabble with frenetic intensity, or plunge to grapple with subterranean forces. The set included three songs from Mr. Young's next album, "Psychedelic Pill," due Oct. 30, and they were openly autobiographical. "Walk Like a Giant" was also a pithy eulogy for 1960s idealism: "We were ready to save the world," Mr. Young sang. Then the weather changed and the white got stained and it fell apart/And it breaks my heart to think about how close we came. It ended with blast after slow blast of the closing chord, dozens of times, turning into slabs of abstract noise. Global Citizen, the Web site and festival, grew out of the Global Poverty Project, which strives to end extreme poverty: the situation of more than 1.4 billion people trying to subsist on less than $1.25 a day. The Global Poverty Project works with nongovernmental organizations worldwide, spanning education, women's rights, public health, including providing mosquito nets and malaria treatment as well as training midwives to help eradicate polio in the three countries where it remains endemic. It was noted that Mr. Young is a polio survivor. Concertgoers received free tickets by enrolling an e-mail address with Global Citizen and then performing certain actions through the Web site, including watching videos, spreading information via social media and doing something for a partner organization. During equipment changes there were video clips, activists and celebrities - among them Katie Couric, Selena Gomez, Olivia Wilde and Katharine McPhee, as well as the economist Jeffrey D. Sachs - detailing poverty-related death tolls and efforts to change them. The concert's hosts called for actions like sending a poverty-related tweet to the presidential candidates. Leaders of organizations from India, Haiti and Somalia got rock-star-size ovations. But the audience was there for the music; Foo Fighters fans started shouting for the band before the Unicef pitch ended. Foo Fighters were playing their last scheduled show for some time, and they romped through it. "I wish we could play all night," said Dave Grohl, the band's songwriter and guitarist. But I'd rather see Neil Young. Mr. Grohl was Nirvana's drummer; with Foo Fighters he combines the brawny riffs and the explosive dynamics of grunge with arena-friendly melodies. The music cycled from Mr. Grohl playing guitar alone to full-band bashes and back; the lyrics seesawed between frustrated fury and a yearning for hope, climbing toward optimism at every opportunity. The Black Keys are terse, savvy revivalists, basing their music on early-1970s blues-rock but also allowing themselves infusions of Hendrix, Stax-Volt soul, glam-rock, garage-rock and a touch of psychedelia. This two-man band - Patrick Carney on drums and Dan Auerbach on guitar and vocals - now has additional musicians onstage, but that doesn't make it any less rigorous. Mr. Auerbach moans, nearly all the time, about woman trouble, reaching back to blues vamps and shuffles; Mr. Carney propels him with elemental no-frills beats. The set dispensed their songs like a jukebox, keeping them short and stopping them as soon as they'd had their say. It also included two versions of "Little Black Submarines" - as a solo, fingerpicking quasi-blues, and then with the band, as a direct homage to Crazy Horse, socking away at the beat. Band of Horses, with a front line of three guitars (or two guitars and a keyboard), has yet to escape the shadow of its obvious model, My Morning Jacket, from its high-tenor lead vocals to its triumphal, multiple-guitar choruses. But its songs - about salvaging love or hope from disaster - were well chosen for this concert. K'Naan's songs, which often included highly melodic rapping, revolve around his two worlds: the strife he left behind in Somalia and his ambition and success in the Americas, including his international hit, "Wavin" Flag," which sounds like both a children's song and an anthem. His version on Saturday added New York City details - "We moved to Harlem/Until the I.N.S. gave us a problem" - before turning to the inspirational. For the concert's finale Mr. Auerbach and Mr. Grohl brought their guitars to join Mr. Young and Crazy Horse in "Rockin" in the Free World"; Band of Horses and K'Naan became a backup vocal choir. The song isn't a simple celebration. It's a juxtaposition of dire conditions in the verses and ironic joy in the choruses. It's Mr. Young's take on the complacent "free world" versus real life, and perhaps a song for those who want tweets to suffice as international actions. It was a clamorous multiguitar blowout and, for those who know the song, a hint of the real work ahead before the world can be saved.