Psiphon is a free and open-source Internet censorship circumvention tool that uses a combination of secure communication and obfuscation technologies, such as a VPN, SSH, and a Web proxy.

Psiphon is a centrally managed and geographically diverse network of thousands of proxy servers, using a performance-oriented, single- and multi-hop routing architecture.

Psiphon, Inc. and the Citizen Lab at the Munk School of Global Affairs, University of Toronto occasionally collaborate on research projects, through the Psi-Lab partnership.

[9][12] The source of funding came from the European Parliament and the US State Department Internet Freedom program, administered by the Bureau of Democracy, Human Rights, and Labor (DRL).

[13] The objective of these grants was to develop Psiphon into a scalable anti-censorship solution capable of supporting large numbers of users across different geographic regions.