The Tokyo subway sarin gas attack in 1995 and the US postal anthrax letter attack in 2001 presented a threat of chemical and biological terrorism all over the world. To realize safe and secure society, the authority should establish a more strengthened crisis management system at national level for civil defense. Detection and identification of the causative agents is very important for countering chemical and biological terrorism from the standpoint of damage minimization. Various kinds of measuring technologies have been used for the on-site detection and laboratory identification of chemical and biological warfare agents (CBWAs). This review highlights the physicochemical and toxic properties of CBWAs, detection and identification requirements for crisis management, and the present status of detection technologies. Efficiency of mass spectrometry is compared with that of other analytical technologies from the standpoint of countering chemical and biological terrorism.