A communications assembly, comprising: a first device operable for a public mobile radio network; a second device operable for a private mobile radio network; and a communications interface module configured to provide a communications conduit between said first and second devices over a local communications medium for routing: a communication originating at said first device through said communications interface module to said second device for transmission over said private mobile radio network; and a communication initiated at said communications interface module to said first device for transmission over said public mobile radio network; characterised in that: said communications interface module is a separate article from said first and second device and is configured to interengage with said second device to provide electrical connection for electronic communication between said communications interface module and said second device, said electrical connection comprising a part of said communications conduit; and further wherein said communications interface module comprises a local network communications module for establishing a communications connection between said first device and said communications interface module, said communications connection comprising a remaining part of said communications conduit. a first device operable for a public mobile radio network; a second device operable for a private mobile radio network; and a communications interface module configured to provide a communications conduit between said first and second devices over a local communications medium for routing: a communication originating at said first device through said communications interface module to said second device for transmission over said private mobile radio network; and a communication initiated at said communications interface module to said first device for transmission over said public mobile radio network; characterised in that: said communications interface module is a separate article from said first and second device and is configured to interengage with said second device to provide electrical connection for electronic communication between said communications interface module and said second device, said electrical connection comprising a part of said communications conduit; and further wherein said communications interface module comprises a local network communications module for establishing a communications connection between said first device and said communications interface module, said communications connection comprising a remaining part of said communications conduit. a communication originating at said first device through said communications interface module to said second device for transmission over said private mobile radio network; and a communication initiated at said communications interface module to said first device for transmission over said public mobile radio network; characterised in that: said communications interface module is a separate article from said first and second device and is configured to interengage with said second device to provide electrical connection for electronic communication between said communications interface module and said second device, said electrical connection comprising a part of said communications conduit; and further wherein said communications interface module comprises a local network communications module for establishing a communications connection between said first device and said communications interface module, said communications connection comprising a remaining part of said communications conduit. said communications interface module is a separate article from said first and second device and is configured to interengage with said second device to provide electrical connection for electronic communication between said communications interface module and said second device, said electrical connection comprising a part of said communications conduit; and further wherein said communications interface module comprises a local network communications module for establishing a communications connection between said first device and said communications interface module, said communications connection comprising a remaining part of said communications conduit.