The paper gives throughput results in terms of capacities per unit bandwidth for a multiaccess spread-spectrum communication system with a large number of users. Various spread-spectrum schemes are included. The direct sequence scheme with a sine pulse as the chip pulse gives the maximum throughput of log2e(= 1.44) bit/Hz. The frequency hopping schemes withM-ary frequency-shift keying have the smallest throughput; assuming detection with side information, forM= 2 the throughput is equal to that of slotted ALOHA (e−1) and decreases asMincreases.