Today, C4 and CAM plants are amongst the world's most important crops for food and fuel, as well as key drivers of ecosystem function in grasslands and arid regions. Tomorrow, C4 and CAM plants are also likely to be major feedstocks for cellulosic biofuel production and lessons from their specialized metabolism are being incorporated into engineering of improved crop performance. Although the basic biochemistry of C4 and CAM photosynthesis has been largely revealed, our current understanding of the developmental process, evolution and systems coordination of C4 and CAM photosynthesis is incomplete. Our knowledge about the adaptation and acclimation of C4 and CAM photosynthesis under diverse environmental conditions is also incomplete. However, it is recognized that the natural evolution of the C4 and CAM pathways provides important insights into ways by which humanity can engineer improved crop performance. To enable C4 and CAM photosynthesis to better serve humanity, systematic and coordinated research on various areas of C4 and CAM biology is urgently needed. In 2013, the symposium will be held at the I-Hotel and Conference Center on the campus of the University of Illinois at Urbana-Champaign from the 6-9th August. The meeting will include field trips to the nearby SoyFACE experimental facility for study of crop responses to climate change (http://www.soyface.illinois.edu/) and the Energy Farm of the Energy Bioscience Institute (http://www.energybiosciencesinstitute.org/). Interested participants may travel on to the International Photosynthetic Congress in St Louis, Missouri, starting Aug 11th. Our plenary and symposium speakers include leaders in the genomics, evolution, ecology and ecophysiology of C4 and CAM plants. They study C4 and CAM species in the context of food crops, biofuels and natural ecosystems. In addition, speakers will be selected from submitted abstracts to report on the newest and most exciting developments in the subject area.