The results of numerical modelling of Schottky barrier DLTS spectra in the case of non-exponential relaxation of the barrier capacitance are presented. The authors' consider the following factors capable of inducing non-exponential relaxation: comparable densities of deep and shallow electronic traps, a substantial electric field dependence of the carrier capture cross sections of deep electronic traps and a non-uniform spatial distribution of electronic traps in a semiconductor. The effect of these on a DLTS spectral band may manifest itself in the band broadening mainly due to a shift of the high-temperature 'shoulder' to higher temperatures, in the appearance of dependences of the shape and position of the DLTS spectral band on the bias voltage applied to the barrier structure, and/or in a non-monotonic character of the above dependences. Since this behaviour of the DLTS band does not follow from the conventional DLTS technique models, the algorithms commonly used to determine the deep trap recombination parameters face some complications. A number of suggestions on how to overcome the complications are made. The complex behaviour of the DLTS band predicted by calculations for the metal-n-GaP Schottky barriers is illustrated by experimental data.