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<i>Fusarium</i> spp. are important pathogens of potato that cause yield losses at planting and in storage following harvest. Surveys from 2007-2011 in Canada showed that <i>Fusarium sambucinum</i> was the most predominant seed-decay pathogen, followed by <i>F. coeruleum</i>, <i>F. avenaceum</i> and <i>F. oxysporum</i>. Isolates of the various <i>Fusarium</i> spp. collected during Canadian surveys were also tested for their sensitivity to thiophanate-methyl (Senator ® PSPT), thiabendazole (Mertect ® SC) and fludioxonil (Maxim® PSP). In 2011, most isolates of <i>F. sambucinum</i> recovered in the seed survey showed resistance to both thiabendazole/thiophanate-methyl and fludioxonil. By contrast, most other <i>Fusarium</i> spp. were sensitive to these products. Isolates of <i>F. oxysporum</i> recovered in these surveys were always sensitive to thiabendazole and thiophanate-methyl, but resistant to fludioxonil. Field and storage studies were conducted to ascertain the impact of fungicide-resistant strains on crop loss and to define potential management strategies. In all cases, treatment of potato seed pieces with mancozeb, difenoconazole or prothioconazole completely controlled seed-piece decay caused by a multi-class resistant isolate of <i>F. sambucinum</i>. Based on our research, knowing the predominant <i>Fusarium</i> spp. in a particular seedlot and their sensitivities to various chemical products would provide growers with important information to use to make disease management decisions.<p><p>Keywords: Fungus, Root-Tuber Crops, Potato