Aquatic Geochemistry provides a medium for the publication of original studies broadly relating to the geochemistry of natural waters and their interactions with rocks and minerals under relatively near Earth-surface conditions. Theoretical experimental and modelling papers dealing with this subject area as well as papers presenting observations of natural systems that stress major processes are appropriate for this journal. 'Letter'-type papers will be considered for rapid publication and a limited number of review-type papers will be included on topics of particularly broad interest or where there may exist an area of current major controversy.