A lead response system is provided comprising a customizable lead delivery rules engine and a customizable escalation rules engine for delivering leads to appropriate responders and re-routing undeveloped leads to different responders. Each delivery rule includes two or more criteria which may be met in order for the lead to be delivered to the responder specified in the particular rule. A lead that is not accepted by the responder to whom it was delivered within a user-defined time frame is re-routed for delivery to a new responder according to a set of escalation rules. The escalation rules may include delivery instructions specifying the new responder or may re-route the lead to the delivery rules engine for delivery to a new responder according to a re-application of the delivery rules.