A vibratory gyroscope comprising a plurality of secondary pickoff transducers (4, 5, 6, 7) which are each sensitive to the secondary response mode, wherein: at least two of the secondary pickoff transducers (4, 5, 6, 7) comprise skew transducers (4a, 5a), being rotationally skewed from their typical positions in which they are aligned with antinodes of the secondary vibration and nodes of the primary vibration and designed to be sensitive to the primary mode and configured to produce an induced quadrature signal in response thereto, the vibratory gyroscope further comprising a differential pickoff amplifier, a comparator and electrical connections between the secondary pickoff transducers (4, 5, 6, 7) and the pickoff amplifier characterized in that: the secondary pickoff transducers (4, 5, 6, 7), electrical connections and differential pickoff amplifier are arranged so that in use: the induced quadrature signal is substantially rejected by the amplifier in the absence of a fault condition, and the differential pickoff amplifier outputs an induced quadrature signal when a fault condition disconnects one of the skew transducers (4a, 5a) from the differential pickoff amplifier, and wherein a first skew transducer and a second skew transducer of said skew transducers have induced quadrature signals with substantially the same phase and magnitude that are combined at inverting and non-inverting inputs to the pickoff amplifier, and wherein the comparator is arranged to compare the quadrature output from the differential pickoff amplifier with a predetermined threshold value and provides a fault indication when the predetermined threshold is exceeded. at least two of the secondary pickoff transducers (4, 5, 6, 7) comprise skew transducers (4a, 5a), being rotationally skewed from their typical positions in which they are aligned with antinodes of the secondary vibration and nodes of the primary vibration and designed to be sensitive to the primary mode and configured to produce an induced quadrature signal in response thereto, the vibratory gyroscope further comprising a differential pickoff amplifier, a comparator and electrical connections between the secondary pickoff transducers (4, 5, 6, 7) and the pickoff amplifier characterized in that: the secondary pickoff transducers (4, 5, 6, 7), electrical connections and differential pickoff amplifier are arranged so that in use: the induced quadrature signal is substantially rejected by the amplifier in the absence of a fault condition, and the differential pickoff amplifier outputs an induced quadrature signal when a fault condition disconnects one of the skew transducers (4a, 5a) from the differential pickoff amplifier, and wherein a first skew transducer and a second skew transducer of said skew transducers have induced quadrature signals with substantially the same phase and magnitude that are combined at inverting and non-inverting inputs to the pickoff amplifier, and wherein the comparator is arranged to compare the quadrature output from the differential pickoff amplifier with a predetermined threshold value and provides a fault indication when the predetermined threshold is exceeded. the secondary pickoff transducers (4, 5, 6, 7), electrical connections and differential pickoff amplifier are arranged so that in use: the induced quadrature signal is substantially rejected by the amplifier in the absence of a fault condition, and the differential pickoff amplifier outputs an induced quadrature signal when a fault condition disconnects one of the skew transducers (4a, 5a) from the differential pickoff amplifier, and the induced quadrature signal is substantially rejected by the amplifier in the absence of a fault condition, and the differential pickoff amplifier outputs an induced quadrature signal when a fault condition disconnects one of the skew transducers (4a, 5a) from the differential pickoff amplifier, and wherein a first skew transducer and a second skew transducer of said skew transducers have induced quadrature signals with substantially the same phase and magnitude that are combined at inverting and non-inverting inputs to the pickoff amplifier, and wherein the comparator is arranged to compare the quadrature output from the differential pickoff amplifier with a predetermined threshold value and provides a fault indication when the predetermined threshold is exceeded.