The (gas + liquid) critical temperature of a number of ethers, esters, and ketones are reported. These values, together with values reported by Quadri and Kudchadker, and Ambrose and co-workers provide a fully extended data set for the development of correlations for predicting the critical temperature of organic compounds containing carbon, hydrogen, and oxygen. Values reported here are compared with values reported in the literature, and it is concluded that many older values, on which a number of predictive correlations are based, are incorrect.