Web-based technologies have enabled companies to reach out to their customers and influence decision making in new and different ways. Personalization has shown promise as an approach to attracting an individual's interest and influencing their decision making, and it can be effectively delivered over the Internet. New technologies allow a rich mix of media, interconnected streams of social conversation between users, and one-on-one interaction between the user and the technology delivering the message. These characteristics can be used to influence a decision maker based on research suggesting that consumers will respond more favorably to individualized messages than generalized ones. This paper focuses on socio-technical aspects of personalization by addressing human and technical issues in the implementation and impact of personalization. We provide a Understand-Measure-Deliver theory of personalization and report a case study of a global company that successfully used personalization to influence consumer decisions in the tourism industry. The findings are that customization based on relevant data provides a personalized experience; customers become product designers and product testers with Web 2.0 technologies; and interaction between a human and the technology amplifies user experience.