This review deals with prodn. of pharmaceutically important compds. through plant cell cultures, organ cultures, genetically transformed root cultures and transgenic plants. A scale-up of in vitro systems and biotransformation of low value substrates to high value products has also been dealt with. Recent developments in transgenic research has opened up the possibility of the metabolic engineering of biosynthetic pathways to produce phyto-pharmaceuticals. Prodn. of novel mols. such as antibodies, vaccines, ribosome inactivating proteins, anti-tumor agents and other biol. active compds. from transgenic plants will be the area of major thrust in the years to come.