H. John B. Birks is Professor in Quantitative Ecology and Palaeoecology at the Department of Biology, University of Bergen and the Bjerknes Centre for Climate Research (Norway), Emeritus Professor at the Environmental Change Research Centre, University College London, and Distinguished Visiting Fellow at the School of Geography and the Environment, University of Oxford. He was Adjunct Professor in the Department of Biology at Queen,s University (Kingston, Ontario) until 2011. Andre F. Lotter is Professor in Palaeoecology at the Institute of Environmental Biology of Utrecht University (The Netherlands), where he is head of the Laboratory of Palaeobotany and Palynology. Steve Juggins is a Senior Lecturer and Head of Department in the School of Geography, Politics and Sociology, Newcastle University where he teaches and researches issues of aquatic pollution, diatom analysis, palaeolimnology, and quantitative palaeoecology. John P. Smol is a Professor in the Department of Biology at Queen,s University (Kingston, Ontario), where he also holds the Canada Research Chair in Environmental Change. He co-directs the Paleoecological Environmental Assessment and Research Lab (PEARL). John Smol was the founding editor of the international Journal of Paleolimnology (1987-2007) and is current editor of the journal Environmental Reviews, and editor of the Developments in Paleoenvironmental Research book series.