Support by brothel leaders and the promotion of a conducive environment for HIV prevention programs within brothel establishments are important to promote a safe working environment for Brothel-Based Female Sex Workers (BB FSWs). This study assesses the effects of a cluster randomized pilot trial examining the use of brothel leaders to improve consistent condom use by FSWs residing in brothels and also assessed the feasibility of implementing a similar intervention on a broader scale. Ten brothels in Abuja, Nigeria were randomized and exposed to the experimental (n=5) and control (n=5) arms of the intervention. The feasibility of the intervention and consistent condom use outcomes by FSWs with different partner types as well as condom negotiation self-efficacy were measured. Condom use outcomes and condom negotiation self-efficacy outcomes were analysed using multi-level mixed regression models. A total of 243 FSWs were recruited into the study (control n=66 and experimental n=177) and 107 of them (44%) were available at 16 weeks follow-up. The intervention demonstrated feasibility and positive outcomes for consistent condom use with boyfriends, casual partners and clients of FSWs were obtained. The interaction effect between condition and time indicated increased consistent condom use with boyfriends in the experimental condition (p=0.02). Adherence to the intervention by the FSWs was moderate with the mean sessions attended at 4.4(SD=2.0). The attrition rate during the intervention was high due to mobility of the FSWs. The intervention showed feasibility and effect outcomes indicate promise in enhancing condom use with steady partners of BB FSWs. The design of HIV prevention interventions may benefit from the inclusion of gatekeepers in the promotion of condom use within the brothel, but an adequately powered phase III trial is needed to inform large-scale implementation of this approach.