Two series of articles are included in the FEBS Journal Special Issue on Signalling: this series is based on the 6th Garvan Signalling Symposium, 15-16 October 2012, whereas the accompanying series is based on an international symposium Ca2+ Signalling and Transport in Health and Disease , which was held in Aarhus, Denmark, 19-20 June 2012. The Garvan Signalling Symposia, held at the Garvan Institute, Sydney, Australia, focus on cellular signalling and its role in human disease. This Special Issue features research and review articles contributed by participants at the 2012 meeting, with FEBS Journal being a major sponsor. This article is protected by copyright. All rights reserved.