Road users’ safety comes out from imperfections of a human-vehicle-road system. Previous research and analyses have proved that the key factor in this system in scope of traffic safety is human factor however it is being emphasized that more attention should be given to road geometry and its surroundings. In many situations existing streets’ geometry regardless of the city area enables drivers to speed and excessive speed is pointed as a key factor in road traffic crashes and injuries in both rural and urban areas. Hence it is of great importance to effectively manage speed and enforce speed limits on existing road network and/or within areas demanding special care. Traffic calming measures (TCM) when applied appropriately can be extremely effective method of speed management but their influence on drivers’ behaviour is very different and depending on the type of measure can cause hazardous reaction. The aim of this paper is to analyse impacts of traffic calming measures on drivers’ behaviour. Research area was located in city of Bialystok, Poland and included a group of commonly applied measures such as: speed humps, speed cushion, speed cameras, raised median island, raised pedestrian crossings and raised intersection. Measurements of instantaneous speed, acceleration, deceleration and route tracking data were undertaken to develop the investigation.