Yes, they can be very effective when deployed properly. The American Bankers Association (ABA) recommends that uniformed security personnel be posted outside the branch instead of inside. The guard might prevent the crime because the robber was hesitant to walk past the guard to enter the bank and perpetrate a robbery. Plus, an escape route could be observed and reported. The ABA suggests that security guards posted inside the branch also serve as a significant deterrent to robbery. Positioning the officer near the main door or lobby area allows the guard to be easily seen while presenting a customer-friendly crime prevention presence.