A multi-mode speech communication system having a plurality of different operating modes, each operating mode associated with one of a plurality of different speech applications (108; 308, 401), the system comprising: a speech service compartment that contains a plurality of system users; a plurality of input microphones within the service compartment that receive speech from the system users as an input; a plurality of output loudspeakers within the service compartment that provide audio outputs to the system users; a signal processing module in communication with the speech applications and including: a. an input processing module that processes microphone input signals received from the plurality of input microphones to produce a set of user input signals for each speech application that are limited to currently active system users for that speech application, and b. an output processing module that processes application output communications from the speech applications to produce loudspeaker output signals to provide the audio outputs to the system users, wherein for each different speech application, the loudspeaker output signals are directed only to system users currently active in that speech application; wherein the signal processing module dynamically controls the processing of the microphone input signals and the loudspeaker output signals to respond to changes in currently active system users for each speech application, characterised in that the signal processing module is capable of operating in a plurality of the different operating modes at the same time, and the signal processing module is configured to enhance user input signals for each speech application to maximize speech from system users of that speech application and to minimize audio sources other than those associated with that speech application. a speech service compartment that contains a plurality of system users; a plurality of input microphones within the service compartment that receive speech from the system users as an input; a plurality of output loudspeakers within the service compartment that provide audio outputs to the system users; a signal processing module in communication with the speech applications and including: a. an input processing module that processes microphone input signals received from the plurality of input microphones to produce a set of user input signals for each speech application that are limited to currently active system users for that speech application, and b. an output processing module that processes application output communications from the speech applications to produce loudspeaker output signals to provide the audio outputs to the system users, wherein for each different speech application, the loudspeaker output signals are directed only to system users currently active in that speech application; a. an input processing module that processes microphone input signals received from the plurality of input microphones to produce a set of user input signals for each speech application that are limited to currently active system users for that speech application, and b. an output processing module that processes application output communications from the speech applications to produce loudspeaker output signals to provide the audio outputs to the system users, wherein for each different speech application, the loudspeaker output signals are directed only to system users currently active in that speech application; wherein the signal processing module dynamically controls the processing of the microphone input signals and the loudspeaker output signals to respond to changes in currently active system users for each speech application, characterised in that the signal processing module is capable of operating in a plurality of the different operating modes at the same time, and the signal processing module is configured to enhance user input signals for each speech application to maximize speech from system users of that speech application and to minimize audio sources other than those associated with that speech application.