A radar system for the detection of drones, the system comprising: at least one receive antenna, the or each antenna being arranged to receive radiation from at least one region of interest; at least one transmit antenna, arranged to transmit into the at least one region of interest; transmitter circuitry arranged to generate a waveform for transmission, and to send a signal comprising the waveform to the or each transmit antenna; receive circuitry connected to the or each receive antenna and to a processor, wherein the receive circuitry is arranged to demodulate signal returns received by the receive antenna(s), and to provide the demodulated signals to a processor, characterised in that the processor is arranged to: process the demodulated signals in a first process using a Doppler frequency filter to detect and locate moving objects commensurate with the body of a drone, and to store time and location of the detections indicative of moving objects therefrom, wherein using the Doppler frequency filter comprises processing the demodulated signals to remove any detections indicative of objects that are moving faster than a predetermined speed; process the demodulated signals in a second process to look for signal returns indicative of a preliminary target having a rotational element on a drone and to identify a location of the preliminary target from such returns; and, should a detection indicative of the preliminary target be found in the second process, attempt to match a location of the preliminary target with a location of a detected moving object from the first process, and to provide a confirmed detection of a drone at the location if a location of the detected moving object from the first process matches with the location of the detection of the preliminary target from the second process. at least one receive antenna, the or each antenna being arranged to receive radiation from at least one region of interest; at least one transmit antenna, arranged to transmit into the at least one region of interest; transmitter circuitry arranged to generate a waveform for transmission, and to send a signal comprising the waveform to the or each transmit antenna; receive circuitry connected to the or each receive antenna and to a processor, wherein the receive circuitry is arranged to demodulate signal returns received by the receive antenna(s), and to provide the demodulated signals to a processor, characterised in that the processor is arranged to: process the demodulated signals in a first process using a Doppler frequency filter to detect and locate moving objects commensurate with the body of a drone, and to store time and location of the detections indicative of moving objects therefrom, wherein using the Doppler frequency filter comprises processing the demodulated signals to remove any detections indicative of objects that are moving faster than a predetermined speed; process the demodulated signals in a second process to look for signal returns indicative of a preliminary target having a rotational element on a drone and to identify a location of the preliminary target from such returns; and, should a detection indicative of the preliminary target be found in the second process, attempt to match a location of the preliminary target with a location of a detected moving object from the first process, and to provide a confirmed detection of a drone at the location if a location of the detected moving object from the first process matches with the location of the detection of the preliminary target from the second process. process the demodulated signals in a first process using a Doppler frequency filter to detect and locate moving objects commensurate with the body of a drone, and to store time and location of the detections indicative of moving objects therefrom, wherein using the Doppler frequency filter comprises processing the demodulated signals to remove any detections indicative of objects that are moving faster than a predetermined speed; process the demodulated signals in a second process to look for signal returns indicative of a preliminary target having a rotational element on a drone and to identify a location of the preliminary target from such returns; and, should a detection indicative of the preliminary target be found in the second process, attempt to match a location of the preliminary target with a location of a detected moving object from the first process, and to provide a confirmed detection of a drone at the location if a location of the detected moving object from the first process matches with the location of the detection of the preliminary target from the second process.