Nematodes often still require morphological identification, partly because verified sequences are only available for only a few species, and partly because the few sequences available are not always diagnostic. Morphological identification often involves fixation with formalin, which makes subsequent molecular work difficult with standard techniques. There is thus an ongoing issue of tying sequences to morphologically-identified specimens, which in turn contributes to the dearth of verified sequences. This talk describes the results of recent studies of methods for extracting genetic material from fixed Root-Knot Nematodes of different ages. We have developed specialist techniques to successfully extract DNA sufficient to identify RKN species collected some time ago and fixed for a considerable period of time. This method seems able to obtain genetic material from a range of fixed samples, but not all. Here we describe how to fix nematodes so that genetic material will still be available.