The problem of graffiti vandalism is a relatively recent one and has often been tackled with a methodology the effectiveness of which had not been adequately tested. Following on a specific campaign of experimentation carried out in the historical city centre of Bologna we have put a comprehensive operational manual together which is effective for the removal of the various types of graffiti on the different building materials both historical and modern, which provides a useful methodological reference for the planning and economic valuation of this kind of work.