Book excerpt: Natural Products, broadly defined as high value chemical entities derived from plants or microbial sources, have been known and exploited for many years. In recent years, as the need for higher potency and predictability of such products has increased, more sophisticated concentration and isolation procedures have been developed. With the passage of time, such procedures have been rationalized in terms of scientific principles but, in general, theory has followed behind practice, leading at any given time to an absence from the literature of methods which are truly state of the art. Downstream Processing of Natural Products: A Practical Handbook is a highly practical manual which addresses this issue, and guides researchers and industrial workers through the many potential pitfalls of natural product isolation. The contributors to this volume, all of whom have wide practical experience in this field, present state-of-the-art techniques and observations. The three main stages of natural product purification are covered, namely product release, capture, and purification, and both proteins and secondary metabolites are covered. There is special mention of the requirements of the regulatory authorities with respect to Good Manufacturing Practice, and practical guidance is given on scale-up procedures and process scale instrumentation. Downstream Processing of Natural Products: A Practical Handbook will provide essential practical guidance to all those involved in natural product isolation. This includes academic and industrial researchers, postgraduate students and technicians working in the biotechnology field.