Method and system for communication via a computer network

A method and apparatus for communication via a computer network ( 102 ) including registering a plurality of users ( 206, 222, 224 ) with a trusted body ( 110, 210 ). The trusted body ( 110, 210 ) verifies the identity of each user ( 206, 222, 224 ) and generates a random identifier ( 216 ) for each user ( 206, 222, 224 ). A plurality of users ( 206, 222, 224 ) can enter into a dialogue with the other users by means of messages sent over the computer network ( 102 ) via the trusted body ( 110, 210 ). A user ( 206, 222, 224 ) remains anonymous through use of its random identifier ( 216 ) until such time as the user ( 206, 222, 224 ) reveals its true identity. Due to the registration of the users ( 206, 222, 224 ) with the trusted body ( 110, 210 ) a means of non-repudiation of the dialogue by the users ( 206, 222, 224 ) is provided.