The present study details the inclusion of radiative heat-transfer phenomena in the numerical simulation of reactive hypersonic and atmospheric re-entry flows. Truly two-dimensional algorithms are developed for the radiative source term in the governing equations, whereby the determination of the specific intensity field is obtained by means of a numerical integration over directions of propagation of radiation. The one-dimensional slab approximation is lifted, and the analysis presented allows the determination of the radiative characteristics of the entire flowfield, rather than being limited to the stagnation streamline, thereby providing an accurate assessment of two-dimensional relieving effects in the stagnation region. A few preliminary results are presented for the Mach 47 flow over a cylinder, including a comparison of the two-dimensional algorithm with the onedimensional approximation and an emission-dominated case. The effects of improving the modeling of radiative heat transfer are demonstrated. © 1994 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.