Biodegradation is one of the most important in situ processes determining the quality of oil in conventional and unconventional reservoirs or hydrocarbon attenuation in contaminated aquifers. Moreover, microbial processes such as methanogenesis, sulfate reduction, and biofilm formation have significant direct or indirect impacts on oil recovery. Despite these effects, there is yet a significant gap of knowledge about the activity and dynamics of microbial communities in oil reservoirs and hydrocarbon contaminated sites. The topics of interest include but are not limited to mechanisms of anaerobic biodegradation of hydrocarbons, ecology of hydrocarbon degrading microbial communities, food webs and nutrient recycling, degradation processes and controlling environmental factors, and identity-function relationships in microbial communities. This conference is expected to provide better insights into the ecology of oil-degrading microbial communities and develop future research directions in the field. The deadline for registration and abstract submission is April 1, 2020.