Due to its depletion and the environmental damage it causes, hydrocarbons are being replaced by energy from renewable sources. One such form of energy source is Biomass. Biomass is a renewable raw material generated by living organisms and found in agricultural waste in large quantities. The three main components of biomass are cellulose, hemicellulose and lignin. The first two components are sugar polymers, being cellulosic ethanol a desirable goal for converting those. The truth is that the production of cellulosic ethanol has never passed the pilot unit phase, due to the lack of economic competitiveness. New ways must be found to make this viable. From the latest finding of the biomass structure, new biomass processing pathways are being advanced, constituting new biorefinery models, which will make it possible to obtain cellulosic ethanol concomitant with the production of different bioproducts such as xylitol, oligosaccharides, antioxidants and analogues to carbon fiber, etc. Lipid rich biomass is the source of foods oils. With population growth, the amounts of waste volume will increase. It is important to improve the processes of valorization of these residues, through their conversion into alcoholic esters of fatty acids, which can be used as fuel or in other domestic and industrial applications. This volume reviews advances and innovative applications in this field. It will encourage the use of new works and even unpublished works to use biomass or its components for the production of bioproducts and biofuels.