As web sites proliferate, offering more of the same, why does a customer choose one web site over the others? Among other factors, website intelligence offers a viable answer to this question. However, past studies fall short of providing a comprehensive conceptualization or effective metric of website intelligence, limiting our ability to enhance the intelligent aspects of web sites. Integrating prior research findings, we propose website intelligence as a second order construct consisting of three sub-dimensions of content, presentation, and interaction, and develop new measures for these dimensions. Further, we theorize the website intelligence construct as a mediator of the system quality and information quality effects on user perceptions of usefulness and ease of use, and test the proposed model using PLS on data collected from an experiment. The newly developed measure exhibits strong psychometric properties. The results largely support the proposed mediating role of website intelligence.