A cyber-dissident is a professional journalist, an activist or citizen journalist who posts news, information, or commentary on the internet that implies criticism of a government or regime.

At least two nonprofit organizations are currently working to raise awareness of the contributions of cyber-dissidents and to defend them against the human rights violations to which some of them are subjected: Global Voices Online and Reporters Without Borders. The latter has released a Handbook For Bloggers and Cyber-Dissidents and maintains a roster of currently imprisoned cyber-dissidents.

In regions where print and broadcast media are tightly controlled, anonymous online postings by cyber-dissidents may be the only source of information about the experiences, feelings, and opinions of ordinary citizens. This advantage may be offset by the difficulty in assessing the good faith and accuracy of reports originating from anonymous sources.

Recently, social-media tools have been widely credited with igniting pervasive social upheavals, some of which have even brought down governments.