Abstract: A telephony server, comprising an application program executing under an operating system, communicating directly with telephony hardware to implement telephony system control, having an application programming interface including a call to an external program also executing under the operating system, the application program supporting a plurality of instances of the external programs simultaneously, each external program implementing call handling logic for at least one voice communications channel. The application program may communicate with a Web server, wherein said server proactively communicates with the user in dependence on an automated analysis of a status of a user's shopping cart, representing items of interest having an unconcluded transaction status, requesting establishment of an interactive voice communication session.