Outlines the problem of violence in U.S. and British public libraries, including groups incidents, drunks, unruly youths, and irate patrons. Library staff face managerial apathy and reluctance to tackle. Discusses the reasons for violence, suggests measures to reduce threats and deal with incidents, risk assessment, security measures and staff training. Discusses the 2001 survey of library workers view of violence in libraries and compares with the 1995 McGrath survey. (LRW)