The world’s energy markets rely heavily on fossil fuels such as coal, petroleum crude oil, and natural gas for thermal, gaseous, liquid, and solid fuels, as well as chemicals. In addition, because it takes millions of years for fossil fuels to form in the earth, their supplies are finite and subject to depletion as they are a. Biomass is the only known natural, renewable carbon resource significant enough to be used as a replacement for fossil fuels. This chapter provides an overview of the state of the art of essential biomass conversion technologies that are now in use, as well as those that may play a significant role in future renewable energy. One of the most pressing issues with bioenergy is that it needs to be modernized in order to fit into a long-term development strategy. Modern biomass-derived fuels like methanol, hydrogen, and ethanol from lignocellulosic biomass, which can reach competitive cost levels within 1–2 decades, and electricity production via advanced conversion concepts (i.e. gasification and state-of-the-art combustion and co-firing) are particularly promising (partly depending on price developments with petroleum). The gasification approach provides unique opportunities to combine this with low-cost CO2 capture (and storage), resulting in ideas that are both versatile in terms of main fuel input and product mix, as well as the potential for zero or even negative carbon emissions. To accomplish this, more biomass market development, constant policy support, R&D initiatives, and international collaboration are required.