BackgroundThe biomedical prevention of HIV transmission that medical male circumcision confers was confirmed in a clinical trial setting and rolled out in VMMC programmes. Data assessing the effectiveness of this in a programmatic setting is not available. Concerns about possible risk compensation in circumcised males after circumcision have been raised.AimTo determine the effectiveness of medical male circumcision in prevention of HIV transmission and risk compensationObjectives • To determine the characteristics of HIV sero-negative males aged 18-40 years who seek circumcision. • To determine the incidence of HIV in circumcised males aged between 18 -40 years of age in a mass male circumcision setting. • To determine the risk factors associated with HIV sero-conversion among circumcised males aged 18-40 years. • To determine the effect of circumcision on indicators of HIV transmissionMethods The study will be a Cohort study design. Clients seeking circumcision will, upon providing consent, be enrolled in to the study. All will be provided with HIV counselling and testing as is currently the norm. A questionnaire will be administered by trained interviewers, prior to the circumcision. Both will be done on the same day. Two to seven days post circumcision they will be seen to check for any surgical complications as is currently being done in routine practice. There are follow-up visits that will be scheduled for 6 and 12 months post circumcisions. At these visits a questionnaire will be administered as well as an HIV test done. These will require that the participants come back to the clinic. To minimise loss to follow up subjects will be called by telephone or sent SMS reminders as to the days of follow up as well as a designated member of the study team will phone the subjects at least once a month.