Jim Barber FRS, President of the International Society of Photosynthesis Research 2007–2010, died on 5 January 2020 peacefully after a long illness. Jim kept going as long as he could in his incredible energetic way, organizing meetings and writing papers after his cancer diagnosis in 2012. He was desperately trying to write a paper for the Biochemical Society (as he had been awarded the Heatley Medal and Prize for 2020) when I visited him last December. He knew his time had come, but he wanted to keep going.

Jim left school at 16 and later studied for his A-levels at night school. After gaining his BSc in Chemistry at Swansea University, he went to the University of East Anglia for his MSc and PhD, also completing a 1 year post-doc at Leiden University. Jim was appointed lecturer in the Department of Botany and Plant Technology at Imperial College London in 1968 and a full professor in 1979. He then moved to the Biochemistry Department at Imperial, which he headed from 1989 to 1999.

He spent his whole career specializing in research on the light reactions of photosynthesis, culminating in 2004 in the first refined crystallographic structure of Photosystem II, the water-splitting enzyme, in collaboration with Professor So Iwata. He was awarded many honours for his achievements, including Member of Academia Europaea (1989), Foreign Member of the Royal Swedish Academy of Sciences (2003) and Fellow of the Royal Society (2005). In addition to his research, he edited countless books and organized many meetings on photosynthesis. In later years, he focused on artificial photosynthesis in order to develop a technology for solar fuel production, to which end he established the Biosolar lab at the Politecnico di Torino and the Solar Fuels lab in NTU Singapore.

Jim truly was someone who wanted to get on in life and finally fought a battle against cancer. I will never forget that during my last visit to see him before Christmas he was trying to calculate how much ATP he needed to keep going!

Jim is survived by his wife, Lyn, his two children, Neil and Julie, and six grandchildren.