The group of carotenoid-derived signalling molecules termed Strigolactones were first discovered almost 60 years ago and repeatedly rediscovered due to their many wide-ranging functions in plants not least for their important role in rhizosphere communication, seed germination and shoot branching. Research markedly took off in 2008, after the discovery that strigolactones act as phytohormones and since then biochemical, genetic and evolutionary aspects of strigolactone biosynthesis, function, and related signalling pathways have been subject to intense investigations. This month’s special issue, organised and introduced by Shinjiro Yamaguchi, Junko Kyozuka and Yoshiya Seto, focusses on the latest research trends to emerge from this field and contains a series of review articles as well as original research articles extending our knowledge of this fascinating topic.