In addition to the usual characteristics of coals, Coke Strength after Reaction values (CSR) are more and more used in coal trade. The stated values are generally far from the industrial reality and often overestimated through favourable carbonization conditions. Laboratories worldwide use their own devised methodology for coke making, which is cause for concern since CSR results cannot be compared without difficulty. So there is a need to better understand the influence of coal carbonization conditions on coke CSR in order to be competitive in the coal market by means of correct coal value-in-use determination.