The following chapters deal with the chemistry, catalytic poisoning, newer catalyst technologies, and possible future solutions to increase the efficiency of creating high-value products by thermochemically converting gasified biomass (producer gas). Chapter 1 puts emphasis on multifunctional catalysts containing transition metals that are used for renewable fuel production. High-value products such as gasoline-range hydrocarbons, dimethyl ether (DME), aldehydes, isobutane, isobutene and other olefins can be produced with gasified biomass due to the gas containing syngas (H2 + CO). The chemistry and production of these chemicals is discussed in the review. Chapter 2 describes the reactor design of a bench scale system and results after using a Mo/HZSM- 5 catalyst for aromatic hydrocarbon creation. This chapter also discusses issues that came with trying to control the temperature without any reactor intercooling. Chapter 3 shows the feasibility of using a particular multifunctional catalyst with a lab scale system and also shows the importance of certain process variables including temperature, space velocity, gas ratios, and pressure. The subject of the importance of the cleanliness of the producer gas is also discussed so that maximum high-value product yield can be achieved with the greatest efficiency. Chapter 4 discusses the implementation of a bench scale and pilot scale reactor design (both with intercooling) and the results of scale-up when using the catalyst mentioned in Chapter 3. Chapter 5 involves the modelling of an industrialized system with Aspen Plus. The economics of industrial plants to produce hydrocarbons from coal or wood feedstocks at scales of 5, 50 and 5000 tons per day were modeled using CAPCOST.