Protecting personal information in online environments is vital to most individuals, including those in the three distinct age groups of children, adolescents and emerging adults. As each group interacts online, they use different disclosure practices and protection mechanisms to manage and distribute their personal information. After describing self-disclosure and communication privacy management theory (CPM), this chapter examines how privacy management strategies and selfdisclosure practices in online environments differ between children, adolescents and emerging adults. The chapter considers theoretical strengths and weaknesses of CPM and also explores the applicability of the tenets of CPM to online communication in self-disclosure. In concluding, the text argues that a greater understanding of the privacy protection mechanisms employed by children, adolescents and emerging adults will help to strengthen privacy regulation and protection of personal information for each of these specifi c groups. Implications for media literacy, privacy protection practices, online marketing and advertising are presented. Every day, individuals around the world use the Internet for a multitude of reasons, including product research, trip planning, socialising, leisure activities and more. Each of these individuals will interact with various websites and online entities as they embark on fi nding solutions or information to fulfi l their varying end goals. Through the navigation of websites, individuals may fi nd themselves divulging information in exchange for product discounts, educational information, or, in the case of social networks, recommendations as to whom to connect and socialise with. Connecting with users on social networks requires users to disclose important personal information, with this self-disclosed information providing the foundation of the business model employed by social network sites (SNSs), including Facebook.