For a mailorder application, the SPREIN voice I/O system is currently under development. It will accept orders via telephone without any human opera tor interaction. Potential users have to enter their orders by voice, and their speech will be interpreted by a speaker independent isolated word recogniser. In response, the SPREIN system will use a speech sythesiser capable to output unrestricted text on a phoneme basis.

The recogniser and the speech synthesiser are controlled by a dialogue controller interfacing users via a data line to the remote host computer of a mail order company. The remote host computer and the dialogue controller share responsibility for the ordering procedure. While the host computer manages the general flow of control for an ordering procedure, the dialogue controller is in charge of user guidance and assistance during user interaction.