Stephen P. Long, A. Marshall-Colon, and X. G. Zhu

Photosynthesis is a process that all life on earth depends on. Photosynthetic organisms convert more than 109 metric tons of atmospheric CO2 into biomass per year. With the global human population rising from ~7 billion now to 9-10 billion by 2050, the worldwide trend towards a more meat-rich human diet, the loss of harvest and grazing land, and the negative effects of global warming on crop production have put forward the question of whether this incredibly high amount of biomass production can be further increased. This article, together with {1-3}, provides a useful guide to the progress so far in enhancing, and in the long term re-designing, photosynthesis with respect to light energy conversion efficiency, which is a prime target when aiming to increase crop yield.