In life science, bioluminescence and chemiluminescence have become a vital tool for laboratory analysis and biomedical imaging both in academic research and industrial product development. The latest advances in this exciting field, from fundamental research to cutting-edge applications, are explored in this most recent volume of the biannual symposium series, the Proceedings of the 14th International Symposium on Bioluminescence and Chemiluminescence.The volume highlights advances in fundamental knowledge about the origins and mechanisms of naturally occurring luminescence, including luciferases from firefly, beetle, marine, bacterial and fungal sources. Developments in instrumentation are presented, together with a wide variety of optical imaging applications for light-emitting gene expressions in optical imaging, such as imaging of gene expression and protein folding in cells, tissues and live animals. In particular, the various contributors describe in detail the use of light-emitting bacteria and viruses for the detection and therapy of tumors, as was highlighted in the symposium.