ESDU 9801 8 gives data for forty-four liquid halogenated aromatic hydrocarbons. Experimental results drawn from the literature for each compound were fitted with a four term polynomial equation in reduced temperature. The coefficients were also faired with changing molecular structure to ensure the best correlation not only for the individual compounds but also as members of their chemical series. The coefficient correlations also allowed values to be predicted for compounds for which no measured data exist. The equations were used to tabulate thermal conductivity values from the melting point to about 0.9 critical temperature in SI units at 10 K and 10 degree Celsius intervals. The likely uncertainties at various temperatures are assessed and are indicated in the tables. The critical point@ coefficients and sources of the data are given for each compound. The effect of pressure is briefly considered.