A call admission control technique is described which is well-suited for wireless systems providing real-time services over a shared downlink. The call admission control technique considers both multiplexing and multi-user diversity gain. The technique accurately determines the multi-user diversity gain by measuring per-user resource allocation and advantageously maximizes user accommodations under quality-of-service (QoS) as well as location-dependent resource availability constraints. In a further aspect, the call admission control technique is combined with delay-based scheduling, which effectively balances between system efficiency (channel exploitation) and user expectation (e.g., QoS). A system embodying the described call admission control and scheduling techniques can advantageously deliver efficient real-time services and remain robust to different load scenarios that vary according to system dynamics and/or user mobility.