This special issue of the Journal of Quaternary Science comprises a selection of papers from the third meeting of a series on ‘ISOtopes in PALaeoenvironmental reconstruction’ (ISOPAL), themed around Isotopes and Biogenic silica (IBiS). The meeting was held at the British Geological Survey (Nottingham, UK) in April 2007, and consisted of a series of presentations giving methodological approaches to using isotopes in biogenic silica but also specific examples of the application, the majority of which are presented in this issue. © Natural Environment Research Council (NERC) copyright 2008. Reproduced with the permission of NERC. Published by John Wiley & Sons Ltd.