This book examines in detail the recent advances in the understanding of genes isolated from Agrobacterium rhizogenes, metabolic engineering in the production of indole terpenoid alkaloids, the use of elicitors and culture process approaches to increase the production of secondary metabolites, bioreactor design and process intensification, vaccine production and drug delivery systems. And finally, the synthesis of nanoparticles using the hairy root culture method has been discussed and can significantly update the reader's knowledge in the field of hairy root systems and the development of its application.