A system for emulating a subject, to allow a user to interact with a computer generated talking head with the subject's face and voice, said system comprising a processor, a user interface and a personality storage section, the user interface being configured to emulate the subject, by displaying a talking head which comprises the subject's face and output speech from the mouth of the face with the subject's voice, the user interface further comprising a receiver for receiving a query from the user, the emulated subject being configured to respond to the query received from the user, the processor comprising a dialogue section and a talking head generation section, wherein said dialogue section is configured to generate a response to a query inputted by the user from the user interface and generate a response to be outputted by the talking head, the response being generated by retrieving information from said personality storage section, said personality storage section comprising content created by or about the subject, and said talking head generation section is configured to: convert said response into a sequence of acoustic units, the talking head generation section further comprising a statistical model, said statistical model comprising a plurality of model parameters, said model parameters being derived from said personality storage section, the model parameters describing probability distributions which relate an acoustic unit to an image vector and speech vector, said image vector comprising a plurality of parameters which define the subject's face and said speech vector comprising a plurality of parameters which define the subject's voice, the talking head generation section being further configured to output a sequence of speech vectors and image vectors which are synchronised such that the head appears to talk, wherein the system is configured to output an expressive response such that said face and voice demonstrate expression, said processor further comprising an expression deriving section configured to determine the expression with which to output the generated response, and wherein the said model parameters describe probability distributions which relate an acoustic unit to an image vector and speech vector for an associated expression, said expression deriving section being configured to extract expressive features from said response to form an expressive linguistic feature vector constructed in a first space and map said expressive linguistic feature vector to an expressive synthesis feature vector that is constructed in a second space, said expressive synthesis feature vector being related to the said model parameters. convert said response into a sequence of acoustic units, the talking head generation section further comprising a statistical model, said statistical model comprising a plurality of model parameters, said model parameters being derived from said personality storage section, the model parameters describing probability distributions which relate an acoustic unit to an image vector and speech vector, said image vector comprising a plurality of parameters which define the subject's face and said speech vector comprising a plurality of parameters which define the subject's voice, the talking head generation section being further configured to output a sequence of speech vectors and image vectors which are synchronised such that the head appears to talk, wherein the system is configured to output an expressive response such that said face and voice demonstrate expression, said processor further comprising an expression deriving section configured to determine the expression with which to output the generated response, and wherein the said model parameters describe probability distributions which relate an acoustic unit to an image vector and speech vector for an associated expression, said expression deriving section being configured to extract expressive features from said response to form an expressive linguistic feature vector constructed in a first space and map said expressive linguistic feature vector to an expressive synthesis feature vector that is constructed in a second space, said expressive synthesis feature vector being related to the said model parameters.