A method of locating and tracking an RFID tag, comprising the steps of: scanning an operating environment with a first steerable signal beam interrogation signal from a first phase array steerable antenna by stepping the antenna signal beam incrementally through each of a number of direction vectors; storing RFID tag response signals received at each direction vector of the first steerable signal beam in a data matrix including a direction vector of the first steerable signal beam when each response signal is received and an identification of the RFID tag providing the response signal; generating an estimated location of each RFID tag by calculations based upon the data matrix received signal data: characterised in that the method further comprises the steps of: for each estimated location of an RFID tag obtained by the first phase array steerable antenna scanning a subset area of the operating environment by a second steerable signal beam interrogation signal from a second phase array steerable antenna; the selected subset area centered upon the estimated location and with a reduced number of direction vectors stepped through; storing RFID tag response signals in a data matrix including a direction vector of the second steerable signal beam when each response signal is received and an identification of the RFID tag providing the response signal; and triangulating a response signal origin location for each response signal where the identification is the same. scanning an operating environment with a first steerable signal beam interrogation signal from a first phase array steerable antenna by stepping the antenna signal beam incrementally through each of a number of direction vectors; storing RFID tag response signals received at each direction vector of the first steerable signal beam in a data matrix including a direction vector of the first steerable signal beam when each response signal is received and an identification of the RFID tag providing the response signal; generating an estimated location of each RFID tag by calculations based upon the data matrix received signal data: characterised in that the method further comprises the steps of: for each estimated location of an RFID tag obtained by the first phase array steerable antenna scanning a subset area of the operating environment by a second steerable signal beam interrogation signal from a second phase array steerable antenna; the selected subset area centered upon the estimated location and with a reduced number of direction vectors stepped through; storing RFID tag response signals in a data matrix including a direction vector of the second steerable signal beam when each response signal is received and an identification of the RFID tag providing the response signal; and triangulating a response signal origin location for each response signal where the identification is the same. for each estimated location of an RFID tag obtained by the first phase array steerable antenna scanning a subset area of the operating environment by a second steerable signal beam interrogation signal from a second phase array steerable antenna; the selected subset area centered upon the estimated location and with a reduced number of direction vectors stepped through; storing RFID tag response signals in a data matrix including a direction vector of the second steerable signal beam when each response signal is received and an identification of the RFID tag providing the response signal; and triangulating a response signal origin location for each response signal where the identification is the same.