These Proceedings comprise the majority of the scientific contributions that were presented at the VIIth International Congress on Photosynthesis. The Congress was held August 10-15 1986 in Providence, Rhode Island, USA on the campus of Brown University, and was the first in the series to be held on the North American continent. Despite the greater average travel distances involved the Congress was attended by over 1000 active participants of whom 25% were registered students. This was gratifying and indicated that photosynthesis will be well served by excellent young scientists in the future. As was the case for the VIth International Congress held in Brussels, articles for these Proceedings were delivered camera ready to expedite rapid publication. In editing the volumes it was interesting to reflect on the impact that the recent advances in structure and molecular biology had in this Congress. It is clear that cognizance of structure and molecular genetics will be even more necessary in the design of experiments and the direction of future research.