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Washington State is the largest producer of juice grapes, <i>Vitis labruscana</i> cv. ‘Concord’, and second largest producer of wine grapes in the United States. Grapevine leafroll disease (GLD) is the most widespread and economically significant viral disease of wine grapes in the world and in Washington State. Of the different species of this disease complex, <i>Grapevine leafroll associated virus-3</i> (GLRaV-3) is the predominant virus associated with GLD in wine grapes. Little is known about the occurrence of GLRaVs in juice grapes in Washington, with the first record of the GLRaV-3 in Concords occurring in 2006. The discovery of this virus in Concord vineyards highlighted the lack of knowledge of the occurrence of viruses in Concord grapes in Washington. Various Concord vineyards were surveyed in 2010 and 2011. Samples were taken randomly in each vineyard with a total of 400 samples taken in total (≈33 samples per vineyard). Each sample was tested for 16 different viruses that have been detected in wine grapes in Washington State. All denatured extract was tested for virus presence by RT-PCR and samples that tested positive were either sequenced directly or cloned and sequenced, depending on DNA quality. Thus far, six viruses have been detected; GLRaV-2, GLRaV-2rg, GLRaV-3, GLRaV-4, GLRaV-9, and grapevine virus A. The most common virus found was GLRaV-3 (50%). In 2012, more samples will be taken in new vineyards further away from the current study area. Mealybug and scale insects will also be tested to help assess their role in vectoring of viruses. <p><p>Keywords: Virus-Viroid, Fruits-Nuts, Grape