An interlaboratory comparison of measurements on three types of commercially available polarisation maintaining fibres was performed in the framework of COST 217. The obtained accuracy and reproducibility for the parameters as the mode field diameter, cutoff wavelength and chromatic dispersion was in the same range for these high birefringent fibres as for the conventional circular single mode fibres. Two setups were tested for the simultaneous determination of the birefringence and modal birefringence. The results characterising the polarisation properties of the fibres are presented in a 6-term Sellmeier expansion of the refractive index.