The barley foliar diseases, scald (Rhynchosporium secalis), the net form of net blotch (NFNB, Pyrenophora teres f. teres) and the spot form of net blotch (SFNB, P. teres f. maculata) are caused by three highly variable fungal pathogen populations that can evolve rapidly to adapt to changing varieties and/or fungicide usage. If not managed properly, each disease can cause serious damage to infected crops and, if left uncontrolled, can develop into more serious problems over larger areas in subsequent years making future control even more problematic. This surveillance and monitoring project addresses an important component of an overall management strategy aimed at suppressing these diseases. By developing a better understanding of variation in the pathogen population, the project will provide early warnings to barley breeders, growers and others of new pathogenic changes so that more effective action can be taken to counter the threat.