In this paper, we derive new bounds on the throughput efficiency of Greedy Maximal Scheduling (GMS) for wireless networks of arbitrary topology under the general k -hop interference model. These results improve the known bounds for networks with up to 26 nodes under the 2-hop interference model. We also prove that GMS is throughput-optimal in small networks. In particular, we show that GMS achieves 100% throughput in networks with up to eight nodes under the 2-hop interference model. Furthermore, we provide a simple proof to show that GMS can be implemented using only local neighborhood information in networks of any size.