The interactive nature of the Internet is the key to building a relationship with customers. Interactivity is primarily suited for increasing consumers' satisfaction with a business relationship. Mass customization web sites incorporate a high level of interactivity in the site design. This study was conducted due to the lack of research examining mass customization and satisfaction.;The expectancy disconfirmation model of satisfaction was used as the framework to examine consumer satisfaction. Among the interactivity characteristics, the concept of choice was applied to develop Internet mass customization shopping sites.;The purposes of this study were: (1) to investigate consumer satisfaction with a mass customized Internet apparel shopping site with varying degrees of interactivity, (2) to test a satisfaction model on a mass customized Internet apparel shopping site, (3) to find the relationship of beliefs about Internet shopping to antecedents and consequences of satisfaction, and, (4) to examine the relationship of desire for unique consumer products to antecedents and consequences of satisfaction.;A mass customized children's apparel site was modified to have two levels of choice for selection of clothing design options. Adults who had purchased children's clothing and shopped via the Internet for any product were participants for this study. Data from 208 respondents were used for the statistical analysis.;Findings indicated that consumer's expectations for mass customization were divided into positive and negative aspects. The more interactive customization site was more positively evaluated than the less interactive customization site. The less interactive customization site yielded greater behavioral consequences than the more interactive customization site.;Negative expectations for the mass customized Internet apparel site were related to positive and negative perceived performance but failed to predict satisfaction and disconfirmation. Perceived performance was a significant outcome of treatment effects, a strong predictor of disconfirmation and satisfaction, and a mediating variable of disconfirmation and satisfaction. Disconfirmation strongly predicted satisfaction, and satisfaction strongly predicted behavioral consequences. The individual characteristics of beliefs about Internet shopping and desire for unique consumer products were significant factors predicting consumers' expectations, perceived performance, satisfaction, and behavioral consequences.