From 2003-2010, Steffen was Executive Editor at the website Worldchanging. Worldchanging practiced "solutions-based journalism." The nonprofit announced the goal of its work was to highlight new solutions to what the editorial team saw as the planet's most pressing problems, rather than to spread news of those problems or critiques of their causes.
The site won or was nominated for a number of awards and prizes, including: 2005 won the Utne Independent Press Award; 2006, finalist for a Webby for Best Blog; 2007 finalist for a Webby for Best Magazine, as well as for Bloggie awards for Best Group Weblog and Best Writing for a Weblog; won the Green Prize for Sustainable Literature for its book; won Organic Design Award; Prix Ars Electronica nominee; 2008 named a Webby Official Honoree.
In November 2006, Steffen published a survey of global innovation, Worldchanging: A User's Guide for the 21st century (ISBN 978-0810930957) with a foreword by Al Gore, design by Stefan Sagmeister and an introduction by Bruce Sterling. A second, updated edition was published in 2011 with a foreword by Van Jones and an introduction by Bill McKibben
In 2012, Steffen released Carbon Zero: Imagining Cities That Can Save the Planet, a book which explored the innovations and policy changes a North American city would need to make to become carbon neutral.
Steffen is a frequent public speaker and has spoken at TED, Poptech, Design Indaba, Amsterdam's PicNic, The Royal Geographical Society and New Delhi's Doors of Perception. As well as keynote addresses at industry events like the AIGA and IDSA national conferences, O'Reilly's Emerging Technologies (eTech), FOO Camp and the Business Expo Bright Green held during the Copenhagen Climate Summit. Steffen has keynoted three different South by Southwest conferences (SxSW). Steffen has also spoken at universities including Harvard, Yale, Oxford, Stanford and the London School of Economics.
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- "designBytes: 10.30.06 | Industrial Designers Society of America". IDSA. Retrieved 2012-03-10.
- "ETech 2009: Sustaining the American Family â€" O'Reilly Conferences". En.oreilly.com. Retrieved October 18, 2011.
- "Technologies for Sustainable Growth – Bright GreenProduktside – DI – Organisation for erhvervslivet". Brightgreen.dk. April 28, 2009. Retrieved October 18, 2011.
- "Alex Steffen and Bruce Sterling | South by Southwest Interactive 2005". Itc.conversationsnetwork.org. March 15, 2005. Retrieved October 18, 2011.
- "Alex Steffen". Sxsw Eco. Retrieved 2012-03-10.
- "OOS News | Sustainability Leaders Blog". Yalesustainabilityleaders.wordpress.com. Retrieved October 18, 2011.
- "The Hidden Future of Cities - Video and audio - News and media - Home". .lse.ac.uk. Retrieved 2012-03-10.
- Alex Steffen's website
- Lavin Agency page for Alex Steffen
- Alex Steffen's 2011 TED talk on carbon-zero cities
- Video of Steffen's 2006 talk at the TED conference