The increased knowledge about the structure of genomes in a number of species, about the complexity of transcriptomes, and the rapid growth in knowledge about mutant phenotypes have set off the large scale use of transgenes to answer basic biological questions, and to generate new crops and novel products. Bioengineering and Molecular Biology of Plant Pathways includes twelve chapters, which to variable degrees describe the use of transgenic plants to explore possibilities and approaches for the modification of plant metabolism, adaptation or development. The interests of the authors range from tool development, to basic biochemical know-how about the engineering of enzymes, to exploring avenues for the modification of complex multigenic pathways, and include several examples for the engineering of specific pathways in different organs and developmental stages.