Discovery of carbon nanotubes has great impact on the development of newer methodologies and devices useful for the analysis of various types of chemicals. The functionalisation of CNTs with biomolecules related to chemical and biological warfare agents makes these useful for the detection of these agents. The detection sensitivity can be increased manyfold. Various types of chemical and biological sensors were developed using various type of carbon nanotubes as well as nano particles of different metals. © 2008, DESIDOC.