The prohibitions of chemical and biological weapons have been codified in two international treaties, the Chemical Weapons Convention (CWC) and the Biological Weapons Convention (BWC). Against the background of renewed discussions among BWC states parties about compliance and verification measures for the BWC, this paper asks to what extent the CWC with its complex verification system might serve as a model for verification of the BWC. To this end the first section of the paper will outline similarities and key differences between the two treaties. This will be followed in section two by a brief discussion of the CWC verification system with both routine and non-routine verification elements. Section three will analyze the organizational aspects of verification under the CWC and section four will highlight the impact of science and technology on the evolution of verification under the CWC. The final section will summarize the argument and provide an assessment of the suitability of the CWC as a model for verification under the BWC.