Although effective public agency Web sites are expected to contribute positively to public service quality outcomes, the underlying etiology is not simple and needs to take into account additional factors both from within and outside the organization. Exploration of this relationship must begin with a more nuanced understanding of Web-site effectiveness than the ones employed in the extant literature. Therefore, to examine the relationship between Web-site effectiveness and public service quality, this chapter investigates two research questions: (1) How can the relationship between Web-site effectiveness and service quality be modeled? and (2) Does the effectiveness of the public agency Web site matter for service quality? Relying on the organizational effectiveness and organization technology literatures, the chapter develops a technology demand model that articulates the relationship between service quality and three types of Web-site effectiveness (technical Web-site effectiveness, managerial Web-site effectiveness, and stakeholder Web-site effectiveness). Using data from a national survey of state health and human services agency managers, it employs a simultaneous equation model to examine the relationship between technical effectiveness, managerial effectiveness, and service quality, controlling for multiple organizational and environmental factors. Findings tend to support the technology demand model. Technical Web-site effectiveness and service quality have an influence on managerial Web-site effectiveness. However, results also show that managerial Web-site effectiveness does not affect management perceptions of service quality. Implications of the findings for research and practice are discussed.