Preparing a detailed cause-effect analyses of crashes is possible only if anappropriate computer system is available and if it includes rich databasesabout accidents, traffic, highway features including the surroundingenvironment and weather conditions. Besides data complementarily the systemasserts systematic and automatic analyses together with an easy access todata. Such a system was worked out by the authors and initiated in somePolish cities. Its name is RMIS (Road Management Information System). In thepaper the authors present the system and provide several examples with theultimate goal of road safety improvement.