Methods to analyze chemical warfare agents (CW-agents) and their decomposition products in environmental samples were developed over the last decades. In contrast herewith, procedures for analysis in biological samples have only recently been developed. Retrospective detection of exposure to CW-agents is useful for various applications. It can be envisaged that rapid diagnosis will play a pivotal role in the management of a terrorist attack with CW-agents. In the same context, confirmation of non-exposure of worried citizens is of utmost importance to suppress unrest in the society at large. Also, such methods can be used for forensic analyses in case of suspected terrorist activities ("chemical fingerprints"). These methods will also be valuable in case of a military conflict, e.g., to establish firmly to which chemicals casualties have been exposed to, as a starting point for adequate medical treatment. Finally, the procedures can be used for health surveillance of workers in destruction facilities of CW-agents. This presentation will deal with specific methods currently available for diagnosis of exposure to the most common CW-agents, i.e., nerve agents and mustard agents. Although the presentation will focus on GC/MS and LC/MS analyses of the long-lived protein adducts of these agents, some attention will be paid to metabolites in urine and immuno-chemical detection of DNA-and protein adducts. The utility of the presented methods will be exemplified on the basis of exposure incidents. © 2009 Springer Science + Business Media B.V.