The present invention relates to the field of security of electronic data and/or communications. In one form, the invention relates to data security and/or privacy in a distributed and/or decentralised network environment. In another form, the invention relates to enabling private collaboration and/or information sharing between users, agents and/or applications. Embodiment(s) of the present invention enable the sharing of key(s) and/or content between a first user and/or agent and a second user and/or agent. Furthermore, embodiment(s) of the present invention have application in sharing encrypted information via information sharing services.A number of inventions, aspects and embodiments are disclosed herein.