Co-founder of the International Center for Transitional Justice (ICTJ), Paul Van Zyl has devoted his career to human rights. The South African has been helping his country out of apartheid through the Truth and Reconciliation Commission. Van Zyl calls on America to hold its own commission to "openly and publicly" confront the torture that recently occurred in Guantanamo and elsewhere.

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Senior Advisor on Innovation to Secretary of State Hillary Clinton, Alec Ross, says it's time to reboot US diplomatic efforts abroad. Ross calls for 21st century statecraft based on the innovative use of new media. Previously, Ross co-founded One Economy, a nonprofit devoted to closing the digital divide, and brought his expertise to then Senator Obama?s presidential campaign.

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Erica Williams is a Washington, D.C.-based activist and commentator who currently serves as the Deputy Director of Campus Progress, a project of the Center for American Progress. In this riveting Poptech talk, Williams discusses how the Millennial generation?today?s 18-30 year olds?are re-imagining the nature of political engagement.

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Author and activist Michael Pollan is a passionate advocate for sustainable food. In his compelling PopTech talk, he explores how our industrial food system keeps us overly dependent on fossil fuels, destroys our environment, and makes us sick. Breaking this cycle requires changing our relationship to food - and eating more meals together.

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Will Allen is co-founder and director of Growing Power, Inc., an organization that is transforming the production and delivery of healthy foods to underserved, urban populations. Growing Power operates as an urban farm and education center in Milwaukee, WI, and more recently, Chicago, teaching urban youth how to produce low-cost healthy foods for their communities.

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Marije Vogelzang runs her own food-design laboratory, Proef. She is inspired by everything that surrounds the act of eating ? from the stories and rituals surrounding food preparation to the emotional impact of the texture and color of specific foods. The result? Edible art installations that are at once provocative and intimate.

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Inventor, engineer and MacArthur Genius Grant-winner, Saul Griffith thought he was an eco-prude until he audited his total power consumption and learned he burns three times the energy as the average European. So, he developed Wattzon.com, a free, online tool we can use to gauge our energy footprints and learn how to reduce our roles in climate change.

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2009 PopTech Fellow Jason Aramburu launched re:char in 2005 to develop low-cost technologies that fight climate change while improving the quality of degraded soils. re:char?s systems convert agricultural waste into renewable fuel and into biochar, sequestering atmospheric carbon and improving soil quality.

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2009 PopTech Fellow Eben Bayer is co-founder of Ecovative Design, an initiative that transforms low-value agricultural byproducts into strong biological composites that can be used as biodegradable alternatives to conventional plastics, foams, and packaging materials.

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