A comprehensive carbon dioxide (CO2) corrosion model was developed to predict steel corrosion rate in oil and gas production and transportation systems. Validated with significant amount of experimental data, this model covers the following three scenarios: (1) deaerated CO2 corrosion, (2) aerated CO2 corrosion, and (3) CO2 corrosion with cathodic protection. This paper is focused on summarizing the uniqueness of this model and the links of the above three scenarios. A flow chart is provided to show a straightforward procedure for solving the model equations. Model results are presented and discussed. (C) 2009 Elsevier Ltd. All rights reserved.