[en] The capability to accurately model the natural and perturbed climate is important to the understanding of current-related issues. It is important that all the major physical processes and feedback mechanisms in climate models be evaluated as to their accuracy and limitations. Since the transfer of solar and longwave radiation represents the prime physical process that drives the circulation of the atmosphere and its temperature structure, an evaluation of the modeling of radiative processes is a critical element in the overall evaluation of the models. This paper discusses model comparison studies of infrared radiative transfer models that have been conducted for the purpose of validating and improving these models. 18 refs., 7 tabs