By a combination of gas, paper and thin-layer chromatography, and infra-red, visible, ultra-violet, mass and nuclear magnetic resonance spectrometry, twenty components were detected and investigated in the secretion collected directly from the scent storage reservoir of Nezara viridula . Structures were suggested for eighteen compounds, which normally comprised over 99.9 % of the scent. Three previously identified compounds were confirmed as trans -hex-2-enal, trans - dec-2-enal and n -tridecane. Other major components (1% or more) identified were 4-keto- trans -hex-2-enal, trans -hex-2-enyl acetate, trans -dec-2-enyl acetate and n -dodecane. Trace amounts were found of trans -prop-2-enal, trans -but-2-enal, trans -oct-2-enal, cis -dec-2-enal, 4-keto- trans -oct-2-enal, trans - oct-2-enyl acetate, methyl ethyl ketone, ethyl propyl ketone, methyl heptyl keton, n undecane, and (probably) 4-keto-hex-2-ene. The distribution of the components between the two phases of the scent was studied. The analytical results are discussed in terms of identified constituents of scents from other bugs.