Using an innovative Value-based Self-Disclosure model, this paper examines the motivating factors in consumer decisions to disclose information to a firm requesting personal data online. It focusses on the costs and benefits customers associate with disclosure, and how they relate to privacy concerns. We conducted a controlled experiment in which we manipulated two situational factors: request context and data quantity. We gathered 252 subjects from a panel of French Web users and conducted the experiment online. We used a SEM-PLS approach to validate the measures and test the hypotheses. The quantity of data requested is shown to have no impact on customer value perceptions. The request context (and most notably, greater levels of customization) only has a significant impact on customer enjoyment. Not all four dimensions of value are important and cognitive costs and benefits appear to outweigh affective ones. Two specific perceived value dimensions - usefulness and psychological costs - are major determinants of self-disclosure intentions, and privacy concerns only influence behavioral intention indirectly through these two value dimensions. By encompassing both individual-level (i.e., privacy concern) and contextual-level factors (context of the request, data quantity and perceived costs and benefits), the VSD model offers a comprehensive explanatory framework. In addition to theoretical literature contributions on self-disclosure and privacy issues, our results offer useful implications for e-business, addressing the increasingly urgent question of how to elicit useful personal data from customers without losing their business.