No previous reviews on speciation analysis by high-performance liquid chromatography (HPLC) have dealt solely with the analysis of mercury. The analytical methods are classified on the basis of the sample matrix analysed and deal with: standards and water, marine organisms, biomedical samples and sediments. The relevant technical information, column type, mobile phase, method of detection and detection limit, is presented in tabular form for each of the sample types. The majority of methods use reversed phase chromatography, usually with a buffer, organic modifier and some form of counter ion or complexing agent. Other aspects addressed in this review include sample preparation and instrumental methods of analysis. The review covers publications from 1986 to 1999. (C) 2000 Published by Elsevier Science B.V. All rights reserved.