A variety of causes led air traffic controllers (ATCOs) to instruct go-around procedures. The most frequent are non-stabilized approch, loss of separation or insufficient between aircraft, so that speed monirotring or separations in approaches are particularly significant for an improvement in operational safety. Nowadays, ATCOs use the speed parameter provided by their Controller Working Position (CWP) to apply relevant restrictions to aircraft within their responsibility. This parameter is obtained from the radar tracks and it can differ from the actual speed of the aircraft. The objective of this research was to select appropriate factors infuencing go-around procedures and compare them before and after the introduction of the speed parameter on the CWP display at Barcelona airport.