The global warming problem might be the greatest threat to the future of mankind, and scientists have concluded that Energy related activities are the main cause. Leaks in natural gas transmission facilities are the main sources of fugitive methane emissions which are difficult to mitigate. This book aims at evaluating the possibility of using catalytic reactor t for mitigation of fugitive methane emissions. The focus will be on natural gas compressor station which is a major single source of fugitive methane. Computer modelling of the flow patterns inside the building demonstrated the influence of ventilation openings, ambient temperature and leak location. For a typical building most methane emitted inside will exit through the ridge vent provided the main doors remain closed. When the extraction rate through the ridge vent is controlled, the methane concentration can satisfy the CFRR feed quality. The reactor performance was studied in detail. Two different types of catalysts were evaluated and also a number of parametric studies were conducted. Overall, the proposed technology offers promising results for methane emission abatement.