A method for detecting motion by way of a motion detection system comprising a radar apparatus which is in signal communication with a monitoring and control unit , said radar apparatus being configured to generate an electromagnetic signal suitable for illuminating a predetermined monitored space ; said method being characterized in that it comprises the following steps: - performing at least one scanning cycle on said monitored space by means of said radar apparatus ; - detecting and identifying at least one moving object in said monitored space , said step of detecting and identifying at least one moving object in said monitored space comprising the sub-step of detecting the actual displacement value for each moving object detected inside said monitored space between a detection cycle and the subsequent detection cycle; - providing a threshold value of maximum allowable displacement associated with every moving object detected inside said monitored space between a detection cycle and the subsequent detection cycle; - locating at least one semi-static zone (S) in said monitored space , said step of locating at least one semi-static zone (S) in said monitored space comprising the following sub-steps: - identifying at least one semi-static object which is moving in said monitored space having an actual displacement value equal to or less than said threshold value of maximum allowable displacement between a detection cycle and the subsequent detection cycle for a predetermined number of consecutive scanning cycles, - delimiting said semi-static zone (S) as a localized volume of said monitored space in which said at least one semi-static object has moved during said predetermined number of scanning cycles; - generating an alarm signal only when in said monitored space at least one moving object situated outside said at least one semi-static zone (S) is detected. - performing at least one scanning cycle on said monitored space by means of said radar apparatus ; - detecting and identifying at least one moving object in said monitored space , said step of detecting and identifying at least one moving object in said monitored space comprising the sub-step of detecting the actual displacement value for each moving object detected inside said monitored space between a detection cycle and the subsequent detection cycle; - providing a threshold value of maximum allowable displacement associated with every moving object detected inside said monitored space between a detection cycle and the subsequent detection cycle; - locating at least one semi-static zone (S) in said monitored space , said step of locating at least one semi-static zone (S) in said monitored space comprising the following sub-steps: - identifying at least one semi-static object which is moving in said monitored space having an actual displacement value equal to or less than said threshold value of maximum allowable displacement between a detection cycle and the subsequent detection cycle for a predetermined number of consecutive scanning cycles, - delimiting said semi-static zone (S) as a localized volume of said monitored space in which said at least one semi-static object has moved during said predetermined number of scanning cycles; - identifying at least one semi-static object which is moving in said monitored space having an actual displacement value equal to or less than said threshold value of maximum allowable displacement between a detection cycle and the subsequent detection cycle for a predetermined number of consecutive scanning cycles, - delimiting said semi-static zone (S) as a localized volume of said monitored space in which said at least one semi-static object has moved during said predetermined number of scanning cycles; - generating an alarm signal only when in said monitored space at least one moving object situated outside said at least one semi-static zone (S) is detected. <EOS>