As the United Nations' 21st Conference of the Parties is underway in Paris until Dec. 11, we've heard a number of world leaders -- from President Barack Obama to Pope Francis -- speak out about curbing climate change.
To help highlight the climate talks, photographers Mathias Braschler and Monika Fischer, who are based in Zurich and New York, took dramatic portraits and collected quotes from corporate leaders, politicians and celebrities around the world. The photo series is titled "Act Now."
From Virgin Group founder Richard Branson to supermodel Gisele Bündchen, scroll down to see 19 familiar faces and their personal -- and poignant -- perspectives about climate change.
Quotes were lightly edited for style.