In this book emphasis will be put in the relevance of Plant Biotechnology for producing compounds of pharmaceutical and industrial relevance specifically the contribution of in vitro plant cell cultures for producing recombinant proteins (molecular farming) and compounds produced by plants useful for human and animal health (secondary metabolites) will be discussed. Also the description of some process held by whole plants will be included. The aim will be to provide relevant theoretical frameworks and the latest empirical research findings for professionals and researchers working in the field of Plant Biotechnology, molecular farming and biochemical engineering.