Halide species are one of the most abundant and damaging impurities in syngas derived from coal. Aside from environmental concerns, halides can cause irreversible damage to downstream processes such as particulate filters, catalysts, gas separation membranes, fuel cells and turbines. The current trend towards high‐temperature, dry gas cleaning is making solid sorbents increasingly favourable, and sorbent development must take into consideration the chemical, physical, efficiency and economic aspects of sorbent performance. This article reviews the origins of halides in coals, cleaning requirements and efforts to develop solid sorbents for halide removal for gasification processes. Most research effort to date has concerned (1) the performance and optimization of basic sorbents such as calcium and sodium carbonate and (2) determining the tolerances of catalysts, filters, fuel cells and other plant components to halide impurities. In addition, thermodynamic calculations have been used to compare the performance of a large number of potential sorbents examined using criteria such as conversion, speciation, volatility and regenerability. This exercise confirms alkali and alkaline earth carbonates exhibit the greatest halide conversion at the temperatures demanded by various downstream processes, but these species are not regenerable at high temperatures in the same manner as desulfurization sorbents. Although not previously investigated, scope exists for the investigation of barium carbonate for halide sorption. Halide removal is best performed preceding sulfur removal due to the irreversible inhibition of regenerable desulfurization sorbents by halide species. Copyright © 2011 Curtin University of Technology and John Wiley & Sons, Ltd.