As we look to plants for energy as well as food and feed, demand for major crops is expected to rise 70% by 2050. Yet yield increases from the Green Revolution, a period of agricultural innovation, are stagnating. The Green Revolution’s approaches have reached their biological limits, but photosynthesis—the process of turning light into food—is far below its theoretical effectiveness. Analysis and computer modeling suggest a number of ways the process could be improved, particularly in the context of global atmospheric change. Some of these improvements have already shown promise in field trials. Through bioengineering, we can solve the anticipated shortfall in food, feed and biofuel supply.