With the goal of replacing 30% of the gasoline with fuel from renewable resources by 2030, the production of ethanol and biodiesel will need to increase dramatically in the near future.  This will also require a switch from starch-based to cellulosic ethanol.  The genetic enhancement of biomass crops offers tremendous opportunities to improve both the overall yield of biomass and the efficiency of biomass conversion.  The most efficient way to achieve this is through a plant breeding program able to efficiently incorporate molecular genetic data on specific combinations of alleles, whereby the selection is based on individual genes as opposed to large chromosomal regions that contain QTL.  This relies on the ability to identify useful alleles for key traits.  Advances in genomics and analytical chemistry are offering new opportunities to achieve this, including forward and reverse genetics followed by high-throughput screens for traits of interest, the availability of genome sequences, and the ability to exploit syntenic relationships between genomes of relates species.  A high-throughput forward genetics screen of maize for variation in cell wall composition has resulted in a collection of mutants that can now be evaluated for biomass conversion efficiency.  Since the mutants were generated through transposon insertions, the mutated genes can be efficiently cloned through a PCR-based method used in combination with a sequence database.  The mutant alleles can be incorporated in a breeding program, or the gene sequence can be used to identify natural variants of interest.  The sorghum genome sequence was recently released.  This allows the identification of genes underlying useful quantitative traits, such as the accumulation of sucrose in the stems of sweet sorghum.  The close evolutionary relationship between sorghum, a diploid, and the polyploidy sugarcane may also result in a more efficient way to identify useful alleles in sugar cane.