In this article, Gale Rudd, from Memtech (UK) Ltd a leading membrane system constructor, describes a case study in which a user had a problem with the cost-effectiveness of a small batch microfiltration system used in filtering fermenter broth in the manufacture of cosmetics. A leading International Cosmetics company recently had a problem concerning their existing manual small batch microfiltration system. As design and build specialists, concentrating on evaluating the best available crossflow membranes for a particular application, rather than manufacturing specific membranes, Memtech were seen as objective in their assistance.