Service quality is crucial in retaining customers in both online and traditional stores. However, measuring online service quality is hampered because of the unique aspects of online service quality that are not part of the widely used service quality instrument, SERVQUAL. Identifying these dimensions and assessing their relative importance is the objective of this study. New service dimensions are identified: lack of annoying banners, beneficial search engines, site security, quick response time, and customer recognition. Data dealing with Barnes & Noble.com (www.bn.com) indeed show that all five dimensions are correlated with increased customer loyalty. The data also show that service quality overrides the effects of perceived risk, cheaper prices, and cost to switch a vendor. Data dealing with the traditional Barnes & Noble bookshops and including the new dimension of customer recognition shows that the these new dimensions do not contribute beyond SERVQUAL. These preliminary results suggest that although SERVQUAL is a good instrument for assessing the service quality of traditional stores, additional dimensions are needed to capture some of the unique aspects of online service. The results also confirm that in both traditional and online shops, service quality reduces the effects of perceived risk, cost to switch, and relative price.