Outside of its natural range in South America, the cultivated potato is considered to have a narrow genetic base resulting originally from limited germplasm introductions to Europe. Most potato cultivars are autotetraploid (2n = 4x = 48), highly heterozygous, suffer acute inbreeding depression, and are susceptible to many devastating pests and pathogens, as exemplified by the Irish potato famine in the mid-nineteenth century. Together, these attributes present a significant barrier to potato improvement using classical breeding approaches. A challenge to the scientific community is to obtain a genome sequence that will ultimately facilitate advances in breeding.