AbstractAn interlaboratory study of the calibration of the intensity scales of Auger electron spectrometers has been completed. Thirty‐eight respondees have completed intensity measurements using pre‐calibrated reference materials of Cu, Ag and Au in either the direct or differential modes. The reference material calibrations, made at NPL, involve the recording of true spectra under defined conditions using the metrology spectrometer, in which all instrumental contributions to intensity have been accurately clibrated. The ratio of the spectral intensity form the respondee to that derived at NPL gives the intensity–energy response function of the respondee's instrument. In the direct mode this function may be calibrated at 1 eV intervals from 10 to 2500 eV using any one of the reference materials. By using all three materials it is shown that the average repeatability of the calibrations for the 38 respondees is better than 3% over the energy range 10–2500 eV, improving to < 2% over the range 100–1000eV. The mot serious unknown parameter that has given rise to uncertainty in the intensity function in the past has been the channel electron multiplier ditector efficiency. It is shown here that this term behaves as predicted theoretically and, if ignored, can lead to a factor of two error in intensity. With the present calibration the errors should be reduced to 2% for spectrometers in which there is little internal scattering. In the differential mode twelve peaks are used to define the intensity‐energy calibration. This calibration is less accurate than that in the direct mode and, at the present time, a one‐standard deviation uncertainty of ∼11% is more appropriate. In both modes a loss of intensity owing to multiplier overloading may cause severe errors in the high‐energy peaks.