FeRh exhibits a fascinating structural and magnetic transition from room temperature antiferromagnetism to ferromagnetism at higher temperatures. This complex transition is accompanied by a large change in unit cell volume and entropy. It is of interest in such diverse applications as magnetic recording and magnetic refrigeration. The fundamental nature of the transition is not fully understood either in the bulk or thin film form and numerous interpretations are found in the literature. We shall use polarised neutron techniques to understand the role of strain and using the new sample environment at ISIS study the metamagnetic transition.