Plant biomass degradation is of major importance for many fungi, as this is one of the most abundant and renewable carbon sources on earth. With a global push toward a bio-based economy based on plant biomass conversion, research in this area has obtained enormous momentum. In this chapter, recent insights obtained from fungal genomes and post-genomic studies related to plant biomass degradation will be discussed, focusing in particular on the diversity of the approaches used by different fungi. In addition, an updated overview will be presented of the enzymes currently considered to be involved in the degradation of the plant biomass polymers.