This report discusses the challenges faced by the refining segment in meeting increasingly stringent sulfur regulations. Environmental pressure from multiple angles, including regulations and engine requirements, is pushing sulfur specifications to extremely low levels. Refiners need to act quickly to comply with these regulations, as there will be no place to store high-sulfur fuels in the future. Demand for ultra-low-sulfur on-road fuels has been rising for over a decade in regions at the forefront, and late-comers will eventually catch up. Marine fuel is also contributing to the global trend towards lower sulfur levels. Refiners must almost eliminate sulfur from their products to meet these regulations.