 Clusters will be paired according to their size and demographic characteristics of FSWs and clients. Within each pair, one cluster will be randomly allocated to the intervention and the other to the placebo group using pre-coded envelopes. With an average of 35 FSWs per cluster, the required number of cluster pairs is estimated at 8.7 to detect a 50 reduction in NG prevalence, assuming a baseline prevalence of 25, 80 power and 5 alpha error. 