In order to better understand the role a barrier application plays in an integrated mosquito management program, we applied a bifenthrin barrier application to a large golf course community and evaluated the mosquito population, service requests, and money spent for control from our barrier site as well as a site that was only treated via ground ultra-low–volume (ULV) application or that was left as a control site. Both the barrier application (t  =  2.63, df  =  126, P  =  0.0147) and the ground ULV application (t  =  2.49, df  =  126, P  =  0.0054) significantly reduced mosquito populations compared to the control, but means within treatments did not differ from each other. Mosquito populations in Centers for Disease Control and Prevention traps were reduced by 84% by barrier application and by 52% by ground ULV application at 6 wk posttreatment compared with untreated control. The 2 major species collected during the evaluation period were Anopheles crucians (81%) and Aedes atlanticus (13%). Anopheles crucians was significantly reduced compared with controls for the barrier application (t  =  1.55, df  =  126, P  =  0.003) and ground ULV application (t  =  1.85, df  =  126, P  =  0.052). Aedes atlanticus was significantly reduced by the barrier application (t  =  1.54, df  =  128, P  =  0.002) but not by ground ULV application (P  =  0.083). Overall the barrier application resulted in a significant decrease (χ²  =  35.4, df  =  1, P < 0.0001) in the number of service requests and ground ULV application (χ²  =  5.3, df  =  1, P  =  0.02) compared to the site that was only treated with ground ULV application. The barrier application saved an estimated $2,700. Thus, large-scale barrier applications are an appropriate tool for control of floodwater mosquito populations.