The package was written in 1996. Radioimmunoassay (RIA) is a technique for measuring concentrations of antigens. Although better techniques have subsequently been developed from it, understanding RIA forms the basis for understanding these derivatives. RIA belongs to the family of competition assays which are widely used in science, medicine and related industries to measure the concentrations of biologically active molecules. This package introduces the concepts of RIA and will be useful to anyone wanting to understand how this family of techniques work. To view and download this resource, right click view resource and choose ‘Save Target As’ if using Internet Explorer browser and ‘Save Link As’ if using Firefox. Suitable For: Undergraduate Year One Dr Martin Luck, School of Biosciences. Dr Martin Luck is Associate Professor of Animal Physiology at the University of Nottingham. After reading Animal Physiology at Nottingham, he moved to the University of Leeds to complete a Masters in Steroid Endocrinology and a PhD in Physiology. He carried out post-doctoral research at the University of Southampton and then moved to Hamburg, Germany where he led a research group investigating ovarian follicular development. He returned to Nottingham as an academic in 1990. Dr Luck also has a BA in Mathematics, is a Fellow of the Society of Biology and the Higher Education Academy and is Chair of the Management Board of Bioscience Horizons, the National Undergraduate Research Journal. He has held teaching advisory posts at the University and been a consultant for the Quality Assurance Agency and Higher Education Academy.