Table 5.1 gives reaction rate constants of O(3P) and O(1D) with atmospheric species, that are excerpted from the NASA/JPL panel evaluation No. 17 (Sander et al. 2011) and the IUPAC subcommittee report (Atkinson et al., 2004). In this section, reactions of O(3P) with O2, O3, OH, HO2, NO2, ClO, and those of O(1D) with H2O, N2O, CH4, CFC that are particularly important in atmospheric chemistry, are described.