This study proposes and tests a model that uses privacy concern, trust, and motivations to explain the process leading to information disclosure and the intensity of social network services (SNS) use. Use of SNSs has been shown in our investigation to be negatively correlated to a user’s privacy concern but positively correlated to a user’s trust and motivations. Furthermore, by using a hierarchical regression model, we show that trust accounts for a significant additional amount of variance in SNS use after controlling the variance explained by privacy concern. In addition, motivation accounts for a significant additional amount of variance in SNS use after controlling the variance explained by both privacy concern and trust.