Photo: Joshua Brott

Travis Threlkel paints in light. His canvas: the largest buildings he can find.

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Over the course of 25 years, folk rock icons the Indigo Girls have not only released more than a dozen albums, they have also displayed a staunch dedication to countless social, political and environmental issues, melding music and activism in their own, unique way. Alison Prato talks with band member Amy Ray about how they fight for what they believe in without seeming preachy, the evolution of their music, and the state of women around the world.

There is no "after Ferguson" | Photo: Jon Lowenstein

In advance of the grand jury verdict, photojournalist Jon Lowenstein talks about what he saw in Ferguson, Missouri. With photos and video.

Pia Mancini and her colleagues want to upgrade democracy in Argentina and beyond. Here’s how.

Equality advocate Ash Beckham explains why she’s a chronic over-sharer.

Secrecy is often used as a legal shield to cover up illegal actions by businesses. Anti-corruption activist and TED Prize winner Charmian Gooch explains why we should care — and what we should do.

Investigative journalist Will Potter shares useful resources for anyone looking to find out more about “ag-gag laws,” legislation that seeks to criminalize people for exposing animal cruelty.