These powerful talks offer ideas for rethinking—and hopefully stopping—the spread of HIV and AIDS.

TED Fellow and journalist Evgeny Morozov punctures what he calls "iPod liberalism" -- the assumption that tech innovation always promotes freedom, democracy -- with chilling examples of ways the Internet helps oppressive regimes stifle dissent.

In this moving talk, documentary photographer Kristen Ashburn shares unforgettable images of the human impact of AIDS in Africa.

For the last eight years, pop singer Annie Lennox has devoted the majority of her time to her SING campaign, raising awareness and money to combat HIV/AIDS. She shares the experiences that have inspired her, from working with Nelson Mandela to meeting a little African girl in a desperate situation.

Emily Oster re-examines the stats on AIDS in Africa from an economic perspective and reaches a stunning conclusion: Everything we know about the spread of HIV on the continent is wrong.

Given $50 billion to spend, which would you solve first, AIDS or global warming? Danish political scientist Bjorn Lomborg comes up with surprising answers.

Seth Berkley explains how smart advances in vaccine design, production and distribution are bringing us closer than ever to eliminating a host of global threats -- from AIDS to malaria to flu pandemics.

There is an epidemic of HIV, and with it an epidemic of bad laws -- laws that effectively criminalize being HIV positive. At the TEDxSummit in Doha, TED Fellow Shereen El-Feki gives a forceful argument that these laws, based in stigma, are actually helping the disease spread.

The most successful female British pop musician in history, Annie Lennox has now committed herself to raising awareness of, and supporting actions against, the HIV/AIDS crisis in Africa.

How can mothers with HIV avoid passing it to their kids? In South Africa, Mitchell Besser tapped a new resource for healthcare: moms themselves. The program he started, mothers2mothers, trains new mothers to educate and support other moms.

Sunitha Krishnan is galvanizing India’s battle against sexual slavery by uniting government, corporations and NGOs to end human trafficking.

Armed with bracing logic, wit and her "public-health nerd" glasses, Elizabeth Pisani reveals the myriad of inconsistencies in today's political systems that prevent our dollars from effectively fighting the spread of HIV. Her research with at-risk populations -- from junkies in prison to sex workers on the street in Cambodia -- demonstrates the ...

Emily Oster, a University of Chicago economist, uses the dismal science to rethink conventional wisdom, from her Harvard doctoral thesis that took on famed economist Amartya Sen to her recent work debunking assumptions on HIV prevalence in Africa.

Epidemiologist Seth Berkley is leading the charge to make sure vaccines are available to everyone, including those living in the developing world.

Danish political scientist Bjorn Lomborg heads the Copenhagen Consensus, which has prioritized the world's greatest problems -- global warming, world poverty, disease -- based on how effective our solutions might be. It's a thought-provoking, even provocative list.

Through his William J. Clinton Foundation, former US President Bill Clinton has become a vital and innovative force for world change. He works in four critical areas: health, economic empowerment, citizen service, and reconciliation.

Ernest Madu founded the Heart Institute of the Caribbean, a revolutionary clinic for cardiovascular diseases in Kingston, Jamaica -- revolutionary for offering first-class health care in a developing nation. His next stop: Nigeria.

A woman in sub-Saharan Africa is part of a cutting-edge HIV clinical trial -- but she can't afford a bus ticket to her health clinic, let alone the life-saving antiretrovirals she'll need. Boghuma Kabisen Titanji asks an important question: How can researchers looking for a cure make sure they're not taking advantage of the people most affected ...

In sub-Saharan Africa, HIV infections are more prevalent and doctors scarcer than anywhere else in the world. With a lack of medical professionals, Mitchell Besser enlisted the help of his patients to create mothers2mothers -- an extraordinary network of HIV-positive women whose support for each other is changing and saving lives.

What could you do with the world's smallest 3D printer? Klaus Stadlmann demos his tiny, affordable printer that could someday make customized hearing aids -- or sculptures smaller than a human hair.

Pastor Rick Warren is the author of The Purpose-Driven Life, which has sold more than 30 million copies worldwide. His has become an immensely influential voice seeking to apply the values of his faith to issues such as global poverty, HIV/AIDS and injustice.

Kristen Ashburn's photographs bring us face-to-face with real people in desperate circumstances. Taking us to the intimate spaces of her subjects -- the victims of war, disaster, epidemic -- she elicits the sublime sadness and resolve of human beings in suffering.

Arik Hartmann is tackling the ignorance and misinformation surrounding HIV/AIDS.

In Elizabeth Pisani's latest book, she explores the "improbable nation" of Indonesia.

In Zimbabwe in the 1980s, Mary Bassett witnessed the AIDS epidemic firsthand, and she helped set up a clinic to treat and educate local people about the deadly virus. But looking back, she regrets not sounding the alarm for the real problem: the structural inequities embedded in the world's political and economic organizations, inequities that m...

Hans Rosling unveils data visuals that untangle the complex risk factors of one of the world's deadliest (and most misunderstood) diseases: HIV. By following the data, he suggests a surprising key to ending the epidemic.

Swallowing pills to get medication is a quick, painless and often not entirely effective way of treating disease. A potentially better way? Lasers. In this passionate talk, TED Fellow Patience Mthunzi explains her idea to use lasers to deliver drugs directly to cells infected with HIV. It's early days yet, but could a cure be on the horizon?

Virus hunter Nathan Wolfe is outwitting the next pandemic by staying two steps ahead: discovering deadly new viruses where they first emerge -- passing from animals to humans among poor subsistence hunters in Africa -- before they claim millions of lives.

Musician and activist Bono accepts the 2005 TED Prize with a riveting talk, arguing that aid to Africa isn't just another celebrity cause; it's a global emergency.

Armed with blood samples, high-tech tools and a small army of fieldworkers, Nathan Wolfe hopes to re-invent pandemic control -- and reveal hidden secrets of the planet's dominant lifeform: the virus.