For four days and four nights, with almost 50 presentations and more than 175 posters, the 5th European Nitrogen Fixation Conference continued a tradition of excellence, bringing scientists from diverse fields such as microbiology, biochemistry, computational genomics, and plant physiology together to address the complex problems associated with biological nitrogen fixation (BNF). The conference was hosted by the John Innes Center and the University of East Anglia in Norwich, England and took place from September 6 through 10, 2002. A diverse range of topics was presented, from the evolution of rhizobial genomes to the plant genes involved in bacterial and fungal symbiosis, to the structure of nitrogenase, and to the means by which nitrogen is shuttled between the symbiotic bacteria and the plant. Additionally, sessions involving broader issues, such as nitrogen fertilizer use and work being done in developing countries, brought home the importance of the research being carried out in BNF around the world.