SourSimRL is the industry standard simulator for predicting souring due to microbiological action in water-flooded reservoirs. By reusing reservoir simulation from most commercial and in-house tools, SourSimRL adds microbial activity, H2S and CO2 generation, and transport data while considering rock adsorption, scavenging and other complex effects to predict when and how much H2S can be produced by the wells during field life. Developed over more than 20 years of research in a joint industry project, SourSimRL is currently owned by seven major companies and developed by ESSS in collaboration with them.