As we transition into the twenty-first century, the need for renewable resources to address global energy and food demands has become a major concern. Around the world, scientists are interested in engineering dedicated biomass feedstocks particularly for improved cell wall composition by modifying the major wall components, cellulose and lignin. In this chapter, we review the current knowledge of plant engineering specifically in the area of lignin biosynthesis and composition towards the goal of generating plants optimized for bioethanol production and animal feed. Crops dedicated as biomass feedstocks, i.e., miscanthus, switchgrass, triticals, sorghum and maize, are grasses, which have unique characteristics of making their cell walls ideal sources for bioethanol production. Our understanding of the grass cell wall has significantly improved in the past two decades through studies carried out primarily in maize (. Zea mays). Here, we discuxss several aspects of lignin deposition into the cell wall including the cellular and molecular aspects of lignin biosynthesis. Significant effort was dedicated to identifying the molecular regulators of these processes and the developmental defects resulting from gene modifications. In addition, we demonstrate genetic correlations between genes of the lignin biosynthesis pathway to those involved in cell wall deposition using a gene expression network program. Together this work lays the foundation for future studies addressing the molecular regulation of lignification in the grasses in hopes to develop, through genetic engineering, ideal biomass feedstocks for biofuel production.